Question

Varog ajutatima dau 30p

Answer 1

$1a)=4 x^{2} -4x+1 \\ b) =x^{2} -14xy+49y^2 \\ c)=9+12x+4 x^{2} \\ d)=4 x^{2} +20x+25 \\ e)=9 x^{2} -49 \\ 2a)=3(x+y+z) \\ b)7x(nu...se..vede..bine) \\ c)=(x+1)(2x-5) \\ d)(2x-1)(14x-7)=7(2x-1)^2 \\ 2.) x^{2} +2x+1=(x+1)^2 \\ x^{2} -8x+16=(x-4)^2 \\ 9 x^{2} +12x+4=(3x+2)^2 \\ 4 x^{2} -28x+49=(2x-7)^2 \\ 3 x^{2} +2 \sqrt{3}+1= (\sqrt{3}+1)^2 \\ 2-2 \sqrt{2}x+ x^{2} =( \sqrt{2}-x)^2 \\ 3)4 x^{2} -9=(2x-3)(2x+3) \\ 16 x^{2} -25=(4x-5)(4x+5) \\ 81 x^{2} -49y^2=(9x-7y)(9x+7y) \\ 2 x^{2} -1=(2x-1)(2x+1)$
$5 x^{2} -1= (\sqrt{5}x-1)( \sqrt{5}x+1)$