Question

Calculati: a) (x+4)²+(x-2)²-2x²=
b) (2x-3)²-(3x+5)²+(2x+5)(2x-5)=
c) (x+5)²-(x-2)(x+2)+2(x+1)²=
d) (3+4x)²+4(x-2)²-(x+3)(x-3)=
Va multumesc!

Answer 1

a) (x+4)²+(x-2)²-2x²=x²+8x+16+x²-4x+4-2x²= 4x+20=4(x+5) b) (2x-3)²-(3x+5)²+(2x+5)(2x-5)=(2x-3-3x-5)(2x-3+3x+5)+4x²-25=
=(-x-8)(5x+2)+4x²-25=-5x²-40x-2x-16+4x²-25=-x²-42x-41
c) (x+5)²-(x-2)(x+2)+2(x+1)²=x²+10x+25-x²+4+2x²+4x+2=2x²+14x+31
d) (3+4x)²+4(x-2)²-(x+3)(x-3)=9+24x+16x²+4x²-16x+16-x²+9=2+40x+19x²