Question

27
(2
8. Find the product of a +-a' and (7a+a') and verify the result for a = -2.​

Answer 1

Answer:

a+(-a')=a-a'

thus,

(a-a')×(7a+a')

[(7a×a)+(a×a')]-[(-a'×7a)+(-a'×a')]

(7a²+aa')-(-7aa'-a'²)

7a²+aa'+7aa'-a'²

7a²-a'²+8aa'

Answer 2

Answer:

Step-by-step explanation:

a+(-a')=a-a'

thus,  

(a-a')×(7a+a')

[(7a×a)+(a×a')]-[(-a'×7a)+(-a'×a')]

(7a²+aa')-(-7aa'-a'²)

7a²+aa'+7aa'-a'²

7a²-a'²+8aa'