5/6+3/8=20/24+9/24=29/24=1 5/24
5/9-5/12=29/36-15/36=14/36
7/12-7/20=35/60-21/60=14/60
5/42+10/63=15/126+20/126=35/126
5/24 +7/60=25/120+14/120=39/120
3/4*5/7=15/28
1/8*12=1/8*12/1=12/8
Решение:
( х + 1) ³ = х²·( х +1 )
( х + 1) ³ - х²·( х +1 ) = 0
( х + 1) · ( ( х +1 )² - х²) = 0
( х + 1) · ( х² +1² + 2х - х²) = 0
( х + 1) · (1 + 2х ) = 0
х + 1= 0 или 1 + 2х = 0
х + 1 = 0 2х = -1
х = -1 х = -0,5
Ответ: -1 ; - 0,5.