Question

7(a2+b2)2-15(a4-b4)+8(a2-b2)2

Answer 1

7(a²+b²)² - 15(a⁴-b⁴)+8(a²-b²)²

=> let (a²+b²) = x
(a²-b²) = y

then ,

7x²-15(a⁴-b⁴)+8y²

=> 7x²-15(a²-b²)(a²+b²)+8y²

=> thus , equation formed is = 7x²-15xy+8y²


factorizing this equation using splitting the mid term ,

=> 7x²-7xy-8xy+8y²
=> 7x(x-y)-8y(x-y)

=> (x-y)(7x-8y)

=> now , substitute the Value of x and y in equation

=> (a²+b²-(a²-b²))[7(a²+b²)-8(a²-b²)]

=> (a²+b²-a²+b²)[7(a²+b²)-8(a²-b²)]

=> 2b²[7(a²+b²)-8(a²-b²)]


hope this helps