Question

factorise:
(x² + x)^2 + 4(x² + x) – 21
​

Answer 1

Answer:

(x²+x-3 ) (x²+z+7)

Step-by-step explanation:

(x²+x)² + 4(x²+x) -21

= (x²+x)² + (7-3)(x²+x) -21

= (x²+x)² +7(x²+x) -3(x²+x) -21

= (x²+x){ (x²+x)+7 } - 3{ (x²+x)+7 }

= (x²+x-3 ) (x²+z+7)