=-e^(-x)*x-e^(-x)=e^(-x)*(-x-1)=(ln2;0)=(1/2)*(1-ln2)≈0,153.
Ctg(2x) = 1/√3
2x = arcctg(1/√3) + πn, n∈Z
2x = π/3 + πn, n∈Z
x = π/6 + (πn)/2, n∈Z
(4-x)^2-7=0
16-8x+x^2-7=0
x^2-8x+9=0
D=(-8)^2-4*1*9=64-36=28
x1=8+√28=8+2√7=4+√7
2 2
x2=8-√28=8-2√7=4-√7
2 2
^ - степень
1) 7x^2-7y^2=7(x^2-y^2)=7(x-y)(x+y)
2) 4m^3-4mn^2=4m(m^2-n^2)=4m(m-n)(m+n)
3) x(a-b)+a-b=(a-b)(x+1)
5) m^2(a-2)+n(2-a)=m^2(a-2)-n(a-2)=(a-2)(m^2-n)
6) 2n(x-y)-(y-x)=2n(x-y)+(x-y)=(x-y)(2n+1)
1) 5m^2+10m+5=5(m^2+2m+1)
2) 2xy^2+4xy+2x=2x(y^2+2y+2)
3) 3a-6ab+3ab^2=3a(1-2b+b^2)=3a(b^2-2b+1)