(a-6)(a+6)+(a-6)ˇ2+10a=(aˇ2-36)+(aˇ2-12a+36)+10a==aˇ2-36+aˇ2-12a+36+10a=2aˇ2-2a=2a(a-1)4mˇ3-4(m+2)(4-2m+mˇ2)==4mˇ3-4(4m-2mˇ2+mˇ3+8-8m+8mˇ2)==4mˇ3-4(mˇ3+6mˇ2-4m+8)=4mˇ3-4mˇ3-24mˇ2+8m-32==-24mˇ2+8m-32=-8(3mˇ2-m+4).
Sin4x - cos⁴x = -sin⁴x
sin4x = cos⁴x - sin⁴x
sin4x = (cos²x - sin²x)(cos²x + sin²x)
sin4x = cos²x - sin²x
sin4x = cos2x
2sin2xcos2x - cos2x = 0
cos2x(2sin2x - 1) = 0
1) cos2x = 0
2x = π/2 + πn, n ∈ Z
x = π/4 + πn/2, n ∈ Z
2) 2sin2x - 1 = 0
sin2x = 1/2
2x = (-1)ⁿπ/6 + πk, k ∈ Z
x = (-1)ⁿπ/12 + πk/2, k ∈ Z
Ответ: x = π/4 + πn/2, n ∈ Z; (-1)ⁿπ/12 + πk/2, k ∈ Z.
(х-4)²-25=0 х^2+2х*(-4)+(-4)^2-25=0
16+х^2+(-8)х-25=0
х^2-8х-9=0
х+1=0
х=-1
х-9=0
х2=9
_______
Ответ: х = -1 ; х2=9
1)у=8/х
у=8/1
у=8
2)у=8/х
-1=8/х
х=8*(-1)
х=-8
Ответ:1)х=1;у=8.2)х=-8;у=-1
3х²-6х-3х-х²=-2х+8-4
2х²-9х+2х-4=0
2х²-7х-4=0
√Д=√7²-4×2×4=√49-24=√25=5
х1=-(-7)+5/2×2=12/4=3
х2=7-5/4=2/4=0,5