Factorise:
(i) 12x2−7x+1
(ii) 2x2+7x+3
(iii) 6x2+5x−6
(iv) 3x2−x−4
Lets factorize the given quadratic expressions by splitting their middle terms.
(i) 12x2−7x+1
12x2−7x+1
=12x2−4x−3x+1
=4x(3x−1)−1(3x−1)
=(4x−1)(3x−1)
(ii) 2x2+7x+3
2x2+7x+3
=2x2+6x+x+3
=2x(x+3)+1(x+3)
=(2x+1)(x+3)
(iii) 6x2+5x−6
6x2+5x−6
=6x2+9x−4x−6
=3x(2x+3)−2(2x+3)
=(3x−2)(2x+3)
(iv ) 3x2−x−4
3x2−x−4
=3x2−4x+3x−4
=x(3x−4)+1(3x−4)
=(x+1)(3x−4)