1.1.3 |
Match the columns |
||
1 |
xΛ ∞ |
a) |
x approaches infinity or: x tends to infinity |
2 |
Θ |
b) |
Parentheses; or : round brackets |
3 |
x1 |
c) |
is not equal to |
4 |
x → ∞ |
d) |
x and so on to infinity |
5 |
x=1 |
e) |
x one, or : x sub one |
6 |
≠ |
f) |
X is equal to one, or: x does equal one |
7 |
α , ~ |
g) |
(is) directly proportional to |
8 |
:: |
h) |
I: since, because |
9 |
≡ |
i) |
Is identical with, or is always equal to |
10 |
( ) |
j) |
as (in proportions) |
1.1.4 Say whether the following expressions and signs are true or false:
•a2+b2= c2 a plus b is equal c
•p>q; p is greater than q
•a ≠ b ; a does not equal b; or: a is not equal to b; or: a is not b
•F(x)= 0 f of x(is) identical with zero
•a ≥ b a (is) greater than or equals b
•a ≈ b ; a approximately equals b,
•1, 2, 3, …one, two, three and so on infinity
Unit 2.Operation signs and terms
Look through the table and try to memorize it.
operation |
Signs of operation |
examples |
Names of |
|
|
written |
read |
|
components |
addition |
+ |
plus |
a+b=s |
a and b are |
|
|
|
a plus b is equal to |
addends; or: items; |
|
|
|
s |
or: summands; s- |
|
|
|
|
sum |
subtraction |
- |
minus |
L-1=a |
l-minuend |
|
|
|
Capital L minus |
1 –subtrahend |
|
|
|
small 1 is equal to |
a- difference, |
|
|
|
a |
or: remainder |
multiplication |
* |
multiplied by |
a ×b = a b = ab = c |
a and b are factors |
|
|
|
a times b is equal |
a- multiplicand |
|
|
|
c; or: a multiplied |
b- multiplier |
|
|
|
by b is equal to c; |
c - product |
|
|
|
or: ab equals c |
|
division |
/ |
Divided by; |
a |
a - dividend |
|
|
or : over |
a : b = b = a b = c |
b - divisor |
|
|
|
a divided by b |
c – quotient; or: |
|
|
|
equals c; or: a |
a – numerator |
|
|
|
over b is equal to c |
b – denominator |
|
|
|
|
a/b – a fraction |
6
2.1 Assignments
2.1.1.Memorize the following words and word-groups:
operation sign |
[`Opq`reIS(q)n `saIn] |
знак действия |
operation terms |
[`Opq`reIS(q)n `tq:mz ] |
выражения действий |
addition |
[q`dIS(q)n] |
сложение |
addend / item; |
[q`dend] [`aItem] |
слагаемое |
summand |
[`sAmqnd] |
слагаемое |
sum |
[sAm] |
сумма |
subtraction |
[sqb`trxkS(q)n] |
вычитание |
minuend |
[`mInju(:)end] |
уменьшаемое |
subtrahend |
[`sAbtrqhend] |
вычитаемое |
difference / remainder |
[`dIfr(q)ns] [rI`meIndq] |
разность |
multiplication |
[`mAltIplI`keIS(q)n] |
умножение |
multiplicand |
[`mAltIplI`kxnd] |
умножаемое |
multiplier |
[`mAltIplaIq] |
множитель |
product |
[`prOdqkt] |
произведение |
division |
[dI`vIZ(q)n] |
деление |
dividend / numerator |
[`dIvIdend] |
делимое |
|
[`njHmqreItq] |
|
divisor / denominator |
[dI`vaIzq] [dI`nqmIneItq] |
делитель |
quotient; |
[`kwouS(q)nt] |
частное |
a fraction |
[`frxkS(q)n] |
дробь |
2.1.2. Give the names of components of these operations:
•12 / 4 = 3
•11×20 = 220
•13-6=7
•23+17=40
2.1.3. Match the columns
1 |
+ |
a. |
over |
2 |
- |
b. |
minus |
3 |
* |
c. |
plus |
4 |
≠ |
d. |
multiplied by |
5 |
= |
e. |
as (in proportions) |
6 |
{ } |
f. |
Is identical with, or is always equal to |
7 |
< |
g. |
is equal to, or: does not equal |
8 |
:: |
h. |
is not equal to; or: does not equal |
9 |
≡ |
i. |
Braces |
10 |
/ |
j. |
(is) less than |
7
2.1.4.Write these operations
• add 5 times c 2 times d
• multiply the sum of x and y by z
• subtraction 0.5 times d 0.5 times l
• divide v-w by r times s
2.1.5.Read these expressions
•12 ×30 = 360
•d ÷ m = md
•23 −12 =11
•(12 +8)/ 4 = 5
•[(5 + 3) (12 − 7)]= 40
•[(5 + 3) (12 − 7)]> [(23 +13)÷ 4]
2.1.6. Translate into Russian
A can do a piece of work in 8 days. If B can do it in 10 days, in how many days can both working together do it?
Solution
Let x= the required number of days, then 1x = the part of the work both can do in 1 day;
1x = the part of the work A can do in 1 day; 1x = the part of the work B can do in 1
day:
1x = 18 + 101 , or 109
Solving, x = 409 = 4 94 , the required number of days.
8