1)4a^2-12ab+5b^2 = (2a-3b)^2-4b^2=(2a-3b-2b)(2a-3b+2b)=
=(2a-5b)(2a-b);
2)9c^2-24cd+7d^2=(3x-4d)^2-9d^2=(3c-4d-3d)(3c-4d+3d)=
=(3c-7d)(3c-d);
3)25a^2-20ab-12b^2=(5a-2b)^2-16b^2=(5a-2b-4b)(5a-2b+4b)=
=(5a-6b)(5a+2b);
4)9m^2-30mk+16k^2=(3m-5k)^2-9k^2=(3m-5k-3k)(3m-5k+3k)=
=(3m-8k)(3m-2k).
0.2^2-2*(-5)/0.2-0.2= 0.04+50-0.2=49.84
<span>а)-x2 + 3х - 7 = 0;
x²-3x+7=0
D=3²-4*7<0 - нет действительных </span><span><span>корней
</span>б)0,5x2 -x - 8 = 0.</span>
<span>D=1²-4*0,5*(-8)=1+16=17
два корня
</span>
А)4z(z-5)=4z^2-20z
2)a) (2a-1)^2=4a^2-4a+1
B) (2x^3+2z^2)^2=4x^6+4z^4
Ответ Е.
9^2х+1/3=3^4/5
3^4х+2/3=3^4/5
4х+2/3=4/5
х=0,1