Question

Выберите тождестенно равные выражения.Запишите их в виде тождества. 1.(а-а) ×b и o ; 2.(х+у)×0 и х+у; 3. 5,1х×7 и 35,7х; 4.а-b и b-a; 5.х-у и (у-х)(-1); 6.7 (a-b) и 7а-7b;

Answer 1

1.0=0
3.35,7x=35,7x
5.x-y=x-y
6.7a-7b=7a-7b

Answer 2

1. (а-а) × b и 0

(а-а) × b = 0, since any number subtracted from itself equals 0.

So, the expression (а-а) × b is equivalent to 0.

The identity is: (а-а) × b = 0

2. (х + у) × 0 и х + у

(х + у) × 0 = 0, since any number multiplied by 0 equals 0.

So, the expression (х + у) × 0 is equivalent to 0.

The identity is: (х + у) × 0 = 0

3. 5.1х × 7 и 35.7х

5.1х × 7 = 35.7х, since multiplying a number by 7 is the same as multiplying it by 35.7 (7 × 5.1 = 35.7).

So, the expression 5.1х × 7 is equivalent to 35.7х.

The identity is: 5.1х × 7 = 35.7х

4. а - b и b - a

а - b is the same as -1 × (b - a), since subtracting a number is the same as adding its opposite.

So, the expression а - b is equivalent to -1 × (b - a).

The identity is: а - b = -1 × (b - a)

5. х - у и (у - х)(-1)

х - у is the same as (-1) × (у - х), since subtracting a number is the same as adding its opposite.

So, the expression х - у is equivalent to (-1) × (у - х).

The identity is: х - у = (-1) × (у - х)

6. 7 + (а - b) и 7а - 7b

7 + (а - b) is the same as 7 + а - b, since adding a number to a sum is the same as adding it to each term separately.

So, the expression 7 + (а - b) is equivalent to 7 + а - b.

The identity is: 7 + (а - b) = 7 + а - b

These are the equivalent expressions in the form of identities for the given expressions.