<span>-3а×(-2b)=6ab..................................</span>
<span>4x^2y=3
x</span>²y=3/4
6x²y=6*3/4=4,5
4x^4y²=4(x²y)²=4*9/16=9/4=2,25
Sin a=√3/2 → cos²a=1-3/4=1/4 cosa=1/2
tga=sin a/cosa=√3*2/2=√3 ctga=1/tga=1/√3=√3/3
(x^2+2x-35)/(25-x^2)=((x+7)(x-5))/((5-x)(5+x))=-(x+7)/(5+x)