Объяснение:
7) 2(x+4)+(x+4)²=3
2x+8+x²+8x+16-3=0
x²+10x+21=0
(x+7)(x+3)=0
x=-7 x=-3
8) (x+1)(x+3)+(x-2)²=15
x²+4x+3+x²-4x+4-15=0
2x²-6=0
2x²=6
x²=3
10) 6/(x²+3x+2)+8/(x²+3x-4)=1
x²+3x+2=a
6/a+8/(a-6)=1
6a-36+8a=a²-6a
a²-20a+36=0
D=20²-4*1*36=400-144=256=16²
a1=(20+16)/2=36/2=18
a2=(20-16)/2=4/2=2
x²+3x+2=18
x²+3x-16=0
D=3²+4*1*16=9+64=73
x²+3x+2=2
x²+3x=0
x(x+3)=0
x=0 x=-3
Copyright © 2024 SCHOLAR.TIPS - All rights reserved.
Answers & Comments
Объяснение:
7) 2(x+4)+(x+4)²=3
2x+8+x²+8x+16-3=0
x²+10x+21=0
(x+7)(x+3)=0
x=-7 x=-3
8) (x+1)(x+3)+(x-2)²=15
x²+4x+3+x²-4x+4-15=0
2x²-6=0
2x²=6
x²=3
10) 6/(x²+3x+2)+8/(x²+3x-4)=1
x²+3x+2=a
6/a+8/(a-6)=1
6a-36+8a=a²-6a
a²-20a+36=0
D=20²-4*1*36=400-144=256=16²
a1=(20+16)/2=36/2=18
a2=(20-16)/2=4/2=2
x²+3x+2=18
x²+3x-16=0
D=3²+4*1*16=9+64=73
x²+3x+2=2
x²+3x=0
x(x+3)=0
x=0 x=-3