3.8 Степенные ряды. Практические задачи.
Найти радиус и область сходимости степенного ряда:
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500. |
∞ |
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k · sin |
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∞ |
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501. |
k=1 k2 · 1 − cos |
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502. |
∞ |
k · ln |
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k + 1 |
· (x + 2) |
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503. |
∞ k · 2k − 1 · xk. |
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k=1
504. P∞
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505. P∞
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506. P∞
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k2 + 1 |
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· (x + 1)k. |
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· arctg |
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k + 1 |
k |
507. P∞ k ·
k=1
508. P∞ √k ·
r!
√ √
k + 1 − k · (x − 1)k.
3 Функциональные последовательности и ряды.
509. |
k=1 ln (k + 3 |
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xk. |
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∞ |
ln k + 2k |
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k) |
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∞ |
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∞ |
3k−1 · (x − 2)k. |
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510. (k + 1)2 · xk. |
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511. |
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k=1 |
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512. |
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∞ |
(k − 1)2 |
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(x + 1)k. |
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513. |
∞ |
2k |
xk. |
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=1 (k + 1)3 · |
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k=1 k! · |
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514. |
k=1 k + 1 |
k2 |
xk. |
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515. |
k=1 |
2√k |
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(x |
− |
1)k. |
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∞ |
k − 1 |
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∞ |
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516. |
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∞ k! + 1 |
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517. |
∞ |
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1 |
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k=1 |
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· x |
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=1 k · arctg |
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· x |
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(2k)!! |
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k2 |
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πk |
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· (x + 3)k. |
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∞ |
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518. |
k=1 sin |
k + 1 |
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519. |
k=1 √k + 1 − √k · xk. |
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∞ |
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∞ |
k2 + 1 |
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520. |
kP |
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=1 k4 + k2 + 1 · (x − 1) . |
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521. |
∞ |
k + ln k |
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· (x + 1) |
k |
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=1 k3 + ln3 k |
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522. |
∞ |
k3 + k · 2k |
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xk. |
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· |
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2k + 1 · |
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=1 k4 + k3 |
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3.8Степенные ряды. Практические задачи.
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∞ ln 4k2 + 1 |
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523. |
kP |
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· (x − 1) . |
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k4 + 1 |
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524. |
∞ |
log3 2k + 3k |
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(x + 4)k. |
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k=1 k |
3 |
+ log2 |
(1 + |
4k) |
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∞ |
1 |
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k2 |
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∞ |
525. |
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· xk. |
526. |
k=1 |
+ k2 |
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k=1 |
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527. |
∞ |
1 |
1 |
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k2 |
1 |
· xk. |
528. |
∞ |
k=1 |
+ k |
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· |
k |
k=1 |
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√√
kP |
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∞ |
k + 1 + k |
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529. |
k2 + 1 |
· (x − 2) |
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=1 |
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1 + k12 k3 · xk.
√
√ k3 + k + 1 · xk. k6 + k3 + 1
530. |
kP |
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xk. |
531. |
∞ (k − 1)! + 1 |
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√ |
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=1 k! |
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k + 1 |
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532. |
∞ k√k · xk. |
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533. |
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√√
534. |
∞ |
k2 + k − k2 − 1 |
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(x |
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1)k. |
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√k3 + 1 |
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(k + 1)3 + 1 · xk. k!
ln kk + 2k
ln (kk3 + 1) · xk.
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√ |
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√ |
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· xk. |
535. |
k2 |
+ 1 − |
k2 − 1 |
kP |
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∞ |
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∞ |
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3 |
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· (x + 1)k. |
536. |
√k3 |
+ k − √k3 − 1 |
=1 |
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3 Функциональные последовательности и ряды.
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√ |
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− k |
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537. |
∞ |
k2 + 1 |
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(x |
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3)k. |
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k + 1 |
− |
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∞ |
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(k + 1)2 |
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· xk. |
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538. k=1 |
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2k2 + 1 |
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539. |
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∞ |
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3k |
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· (x − 1) . |
ln |
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+ 1) |
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540. |
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√k |
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541. |
∞ |
2 |
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· sin |
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· (x − 5) |
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4k |
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· |
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542. |
∞ |
2k · arcsin |
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· (x − 3)k. |
=1 |
k2 |
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2k |
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∞ |
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2k + 1 |
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· x . |
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544. |
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3 |
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543. |
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=1 k |
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∞ |
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√k4 + 1 |
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√ |
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· x . |
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546. |
545. |
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+ k |
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547. |
∞ |
arcsin |
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k |
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· (x + 2) |
k |
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=1 |
k2 + 1 |
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πk |
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548. |
∞ |
cos |
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k |
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2k + 1 |
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· x |
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kP |
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k + 1 |
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549. |
∞ arctg |
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2 |
· xk. |
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=1 |
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(k ln k + 1) |
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P∞ 4k + 2k+1 + 1 · xk. k=1 k · ln2(k + 1)
kP |
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∞ sh k · xk. |
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=1 |
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kP |
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∞ |
1 |
· (x − 1) |
k |
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=1 |
sin |
k + 1 |
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3 Функциональные последовательности и ряды.
|
P |
r |
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r |
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! xk. |
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558. |
∞ |
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k3 + 1 |
6 2k3 + 1 |
k=1 k |
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− |
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k3 |
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2k3 |
559. |
k=1 |
ln |
1 + k |
+ |
r |
1 + k − 1! (x − 1)k. |
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P |
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1 |
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∞ |
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1 |
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r!
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kP |
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560. |
∞ |
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− |
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(x + 1) |
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561. |
k=1 |
2k ek |
+ ek − 2 xk. |
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3k e1 − cos 1 xk.
k
k
ln k + 1 + 1 − cos 1 xk. k k
r!
kP |
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∞ |
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564. |
k ek |
− |
1 + |
k |
(x + 3) |
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r!
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k 4 |
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1 |
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565. |
k · 5 |
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1 + |
k |
+ sin |
k |
(x − 1) |
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3 Функциональные последовательности и ряды.
r |
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574. |
1 + |
k |
+ sin |
k |
(x − 1) |
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=1 |
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575.P∞
k=1
576.P∞
k=1
577.P∞
k=1
578.P∞
k=1
579.P∞
k=1
580.P∞
k=1
581.P∞
k=1
r1 + k + r1 + k − 1! |
xk. |
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6 |
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k |
2k ek + ln |
1 + k |
k |
xk. |
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3k ek + ln k +k2 |
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xk. |
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5k + 4 |
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5k ek + ek + ek − 2 |
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(x − 1)k. |
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r!k
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+ |
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− cos |
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ek |
1 + |
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1 + k |
+ 4 |
1 + k − e− k ! (x − 2)k. |
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cosk k |
8 |
1 + k + ln |
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+ k ! xk. |
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k + 1 1 |
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8 |
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3 Функциональные последовательности и ряды.
590. |
k=1 |
r |
1 + k − cos k − ln |
1 + k |
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! x2k. |
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∞ |
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591. |
k=1 |
r |
1 + k2 |
+ |
r |
1 + k2 − 2 cos k ! x2k. |
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4 |
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kP |
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r |
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592. |
∞ |
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k2 |
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+ 1 − |
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k2 |
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∞ |
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593. |
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1 + |
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− cos |
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+ |
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! xk |
. |
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k=1 |
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k2 |
k |
k2 |
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P |
1 |
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∞ |
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594. |
k=1 |
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k2 |
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+ sin |
k |
− arctg |
k |
xk |
. |
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595.P∞ ln 1 + k1 − sin k1 + k12 xk2 .k=1
596. |
k=1 |
2k |
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ek − ln 1 + k − 1 xk . |
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P |
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2 |
1 |
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1 |
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2 |
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∞ |
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∞ |
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2 |
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k2 + 3k + 2 3 |
2 |
597. |
P |
3k |
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− ln |
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+ |
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xk . |
k=1 |
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k2 |
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k |