<span>3x^2+12x-15=0/3</span>
X^2+4x-5=0
<span>X1.2=-2±√4+5=-2±3
</span><span>X1=-5 X2=1</span>
Г)а^2(а- b)-a(b-a)=a^2(a-b)-a(-(a-b))=a^2(a-b)+a(a-b)=(a-b)(a^2+a)=a(a-b)(a+1)
д)36ах(2х-а)+9(а-2х)=36ах(2х-а)-9(2х-а)=(2х-а)(36ах-9)=9(2х-а)(4ах-1)
е)15а(х-2)^2-3а(х-2)=(х-2)(15а(х-2)-3а)=(х-2)(15ах-30а-3а)=(х-2)(15ах-33а)=3а(х-2)(5х-11)
(2a-5b)^2-(5a+2b)^2=(2a^2-2*2a*5b+5b^2)-(5a^2+2*5a*2b+2b^2)=(4a^2-20ab+25b^2)-(25a^2+20ab+4b^2)=4a^2-20ab+25b^2-25a^2-20ab-4b^2=4a^2-25a^2+25b^2-4b^2=21a2+21b^2=21*(0,6)^2+21*(-0,8)^2=21*0,36+21*0,64=7,56+13,44=21
<span>(a+1)</span>³<span>+0,008=((a+1)+0,2)((a+1)</span>²<span>-0,2(а+1)+0,2</span>²<span>)=(а+1,2)(a</span>²<span>+2а+1)-0,2а-0,16)=
(а+1,2)(a</span>²<span>+1,8а+0,84)</span>