115.
1) (3c+1 +c(c-1)) /(c-1) = (3c+1+c^2-c) /(c-1) =
=(c^2+2c+1) /(c-1) =(c+1)^2 /(c-1)
2) (c+1)^2 /(c-1) × 1/(c+1) =
=(c+1)^2 /(c-1)*(c+1) =(c+1) /(c-1)
1
f`(x)=3x²-12=3(x-2)(x+2)=0
x=2 x=-2
+ _ +
------------------(-2)-----------------------(2)----------------
max min
2
f`(x)=3x²-6x-45=3(x²-2x-15)=0
x1+x2=2 U x1*x2=-15
x1=-3∉[-2;6]
x2=5∈[-2;6]
y(-2)=-8-12+90+2=72 наиб
y(5)=125-75-225+2=-173 наим
y(6)=216-108-270+2=-160