Question 92 (xxv)
Factorise the following using the identity a2−b2=(a+b)(a−b).
16x4−625y4
16x4−625y4=(4x2)2−(25y2)2=(4x2+25y2)(4x2−25y2)=(4x2+25y2)[(2x)2−(5y)2]=(4x2+25y2)(2x+5y)(2x−5y)
Question 92 (v)
28ay2−175ax2
Question 92 (xix)
x4−1
Question 92 (xxiii)
x4−y4
Question 92 (vi)
9x2−1