B^2+3b+2=(b+1)(b+2)
d^2-7d-8=(d-8)(d+1)
y^2+2y-8=(y-2)(y+4)
Loga(b)=5 => b=a^5. то loga(a/(a^5)^3) дальше loga(a/a^15)= loga(a^-14)=> -14
-ctg(a+90°)+4ctg(a+270°)-3tg(a+360°) = ? tga=0.65
ctg(a+90°) +4ctg(a+270°)- 3tg(a+360°) = tgα -4tgα - 3tgα = -6tgα = -6*0,65=
<span>= -3,9
</span>