Question

If a+b=1and a-b=7; find 1.a²+b² ,2.ab

Answer 1

Step-by-step explanation:

a+ b= 1 --------(i)

a-b=7-----------(ii)

From sum of equation (i)and (ii)

a+b+a-b = 1+ 7

2a = 8

a =8/2

a = 4

Substitute 'a' in eq (i)

4+b=1

b= 1-4

b = -3

1. a² + b² = ( a + b )² – 2ab

= ( 4-3)²-2(4)(-3)

= ( 1)² +24

= 25

2.ab = 4× -3

= -12

................that's it.