Factorise : 8+6(a+b)−5(a+b)2
Let a+b=x∴ (a+b)2=x2∴ 8+6(a+b)−5(a+b)2=8+6x−5x2=8+10x−4x−5x2=2(4+5x)−x(4+5x)=(4+5x)(2−x)=[4+5(a+b)][2−(a+b)]Substituting the value of x=[4+5a+5b][2−a−b]
Factorise: 4(a+b)−6(a+b)2
Factorise: 36c2−(5a+b)2