Tolong jawab no 3dan 4

3.-5(1)²+4(-2)³+2(12)
-25-128+24=103+24=127
Maaf klu salah

3) - 5a² + 4b³ + 2c
= - 5 ( 1 )² + 4 ( -2 )³ + 2 ( 12 )
= - 5 - 32 + 24
= - 13

4) ( 3x / x-4 ) + ( 4 / x+2 )

= 3x ( x + 2 ) + 4 ( x - 4 )
-----------------------------------
( x - 4 )( x + 2 )

= 3x² + 6x + 4x - 16
----------------------------
( x - 4 )( x + 2 )

= 3x² + 10x - 16
-----------------------
x² - 2x - 8