Question

(4x - 5) (4x - 1) find this by using identity (x+a)(x+b) ​

Answer 1

(x+a)(x+b) = x²+bx+ax+ab = x²+(a+b)x+ab

Comparing (4x-5)(4x-1) with (x+a)(x+b) we get,

x = 4x, a = -5, b = -1

Therefore,(4x-5)(4x-1)

= (4x)²+(-5-1)(4x)+(-5)(-1)

= 16x²+(-6)(4x)+5

= 16x²-24x+5