Question

descompuneți in factori diferența de pătrate :
f)(2x-1)²-16=
g)9-(5x-6)²=
h)(4a-b)²-(2a+3b)²=​

Answer 1

Explicație pas cu pas:

f) (2x-1)²-16=

=[(2x)²-2•2x•1+1]-16=

=4x²-4x+1-16

=4x²-4x-15

g) 9-(5x-6)²=

=9-[(5x)²-2•5x•6+6²]

=9-25x²+60x-36

=-25x²+60x-27

h) (4a-b)²-(2a+3b)²=

=[(4a)²-2•4a•b+b²]-[(2a)²+2•2a•3b+(3b)²]

=16a²-8ab+b²-4a²-12ab-9b²

=12a²-8b²-20ab