Mathematics
Factorise the following:
2a2b2 - 7ab - 30
Factorisation
20 Likes
Answer
To factorise 2a2b2 - 7ab - 30, we want to find two real numbers whose sum is -7 and product is 2 × (-30) = -60. By trial, we see that (-12) + 5 = -7 and (-12) × 5 = -60.
∴ 2a2b2 - 7ab - 30 = 2a2b2 - 12ab + 5ab - 30
= 2ab(ab - 6) + 5(ab - 6)
= (ab - 6)(2ab + 5).
Hence, 2a2b2 - 7ab - 30 = (ab - 6)(2ab + 5).
Answered By
13 Likes