Factorise :
(i) 6x3−8x2(ii) 35a3b2c+42ab2c2(iii) 36x2y2−30x3y3+48x3y2(iv) 8(2a+3b)3−12(2a+3b)2(v) 9a(x−2y)4−12a(x−2y)3
(i) 6x3−8x2=2x2(3x−4)(ii) 35a3b2c+42ab2c2=7ab2c(5a2+6c)(iii) 36x2y2−30x3y3+48x3y3=6x2y2(6−5xy+8xy)(iv) 8(2a+3b)3−12(2a+3b)2=4(2a+3b)2[2(2a+3b)−3]=4(2a+3b)2[4a+6b−3](v) 9a(x−2y)4−12a(x−2y)3=3a(x−2y)33(x−2y)−4=3a(x−2y)3(3x−6y−4)