Используй метод интервалов.
Формула объема усеченного конуса:
V<em>=1/3</em>π h(r<span>1^2</span><em>+</em>r1·r2<em>+</em>r<span>2^2</span>)
(где h- высота, r и r2 - радиусы оснований конуса)
<span>V=1/3*3.14*18(5^2+5*10+10^2)=1/3*3.14*18(25+50+100)=18,84</span>*175=3297 куб. см.
1
b+(8a-b²)/b=(b²+8a-b²)/b=8a/b
a=-49,b=-80 8*(-49)/(-80)=4,9
2
(1/(7a)+1/(2a))*a²/4=(2+7)/(14a)*a²/4=9/(14a)*a²/4=9a/56
a=-2,8 9*(-2,8)/14=-1,8
3
(xy+y²)/(16x)*8x/(x+y)=y(x+y)/(16x)*8x/(x+y)=y/2
x=-6,3;y=-8,5 -8,5/2=-4,25
4
7a/(a-2b)(a+2b)-7/(a+2b)=(7a-7a+14b)/(a²-4b²)=14b/(a²-4b²)
a=8,b=3
14*3/(64-9)=42/55
2)12p³-(1/3)p²-1-3p×(3/3)×p²=
=12p³-(1/3)p²-1-3p×1p²=
=12p³-(1/3)p²-1-3p³=9p³-(1/3)p²-1=
=(1/3)(27p³-p²-3)
4)5x+(1/5)x-20+x+(17/20)-5x=
=(1/5)x-20+x+(17/20)=(6/5)x-(383/20)=
=1/20(24x-383)
6)64-(2ab/(a-8)²)+2ab-(a²/(8-a)²)=
=64-(2ab/(a-8)²)+2ab-(a²/(-(a-8))²)=
64-(2ab/(a-8)²)+2ab-(a²/(a-8)²)=
64(a²-16a+64)-2ab+2a³b-32a²b+128ab
-a²/(a-8)²=
63a²-1024a+4096+126ab+2a³b-32a²b/(a-8)²
Большеникакнесократить!
8)x²+(6/x²)-9-(3(2x-1)/9)-x²=
=(6/x²)-9-((2x-1)/3)=
=(18-27x²-x²(2x-1))/3x²)=
=((18-27x²-2x³+x²)/3x²)=
=((-2x³-26x²+18)/3x²)