Question

(a2+b2) (a2+b2) -( a2-b2) (a2-b2)

Answer 1

(a²+b²)(a²+b²) - (a²-b²)(a²-b²)

= (a²+b²)²-(a²-b²)²

= (a²+b²-a²+b²)(a²+b²+a²-b²)

= 2b²× 2a²
= 4a²b²

Answer 2

Heya

(a² + b²)(a² + b²) - (a² - b²)(a² - b²)

=> (a² + b²)² - (a² - b²)²

Using identity :-

x² - y² = (x + y)(x - y)

Here,

x = a² + b²

y = a² - b²

=> [(a² + b²) + (a² - b²)] [(a² + b²) - (a² - b²)]

Open the ( ) brackets

=> [a² + b² + a² - b²] [a² + b² - a² + b²]

=> [2a²] [2b²]

=> 4a²b²

Hope this helps.