7x - 5x
3 = 3x – x
3
7x - 5x
3 = 3x – x
3 / + x
3
7x - 4x
3 = 3x / -3x
4x - 4x
3 = 0
4x(1 – x
2 ) = 0
4x( 1 – x )(1 + x ) = 0 /:4
x( 1 – x )(1 + x ) = 0
-
x = 0
-
( 1 – x ) = 0
1 – x = 0 / - 1
– x = – 1 / : (- 1)
x = 1
-
( 1 + x ) = 0
1 + x = 0 / - 1
x = – 1