(a-4b)(4b+a) упростить

Question

(a-4b)(4b+a) упростить

Answer 1

4аб+а*2-16б*2-4аб=а*2-16 б*2

Answer 2

(a-4b)(4b+a)=4ab + a^2 -16b^2-4ab=a^2-16b^2= (a-4b)(4b+a)