Explicație pas cu pas:
8)
a)7y³-8y+9y-4y³-11y-6y³=
(7y³-4y³-6y³)+(-8y+9y-11y)=
-3y³-10y
b)8y-17y⁴+5y⁴-6y+4y⁴-5y=
(8y-6y-5y)+(-17y⁴+5y⁴+4y⁴)=
-3y-8y⁴
c)5y-4y⁵+6y-2y⁵-17y+9y⁵=
(5y+6y-17y)+(-4y⁵-2y⁵+9y⁵)=
-6y+3y⁵
d)5y³+3y-9y-5y³+16y-8y³=
(5y³-5y³-8y³)+(-3y-9y+16y)=
-8y³+4y
e)21y²-y⁴-7y⁴-18y²+4y⁴-6y²=
(21y²-18y²-6y²)+(-y⁴-7y⁴+4y⁴)=
-3y²-4y⁴
f)12y³-8y³+y⁵-29y⁵-7y³+5y⁵=
(12y³-8y³-7y³)+(y⁵-29y⁵+5y⁵)=
-3y³-23y⁵
9)
a)7x²-6x-9-2x²+8x+3=
(7x²-2x²)+(-6x+8x)+(-9+3)=
5x²+2x-6
b)4x²-7+3x-8x²-5x+2=
(4x²-8x²)+(-7+2)+(3x-5x)=
-4x²-5-2x
c)21-7x-2x²-x²+12x-8=
(21-8)+(-7x+12x)+(-2x²-x²)=
13+5x-3x²
d)8-6-11x-9x²+5x-2x²=
(8-6)+(-11x+5x)+(-9x²-2x²)=
2-6x-11x²
e)-4x²-9-3x-5x²-7x+2=
(-4x²-5x²)+(-9+2)+(-3x+7x)=
-9x²-7-10x
f)-3x+5-x+4x²-16-7x²=
(-3x-x)+(5-16)+(4x²-7x²)=
-4x-11-3x²
10)
a)5x³-7x+8-6x-11x³-10-x³=
(5x³-11x³-x³)+(-7x-6x)+(8-10)=
-7x³-13x-2
b)9x-4x³-4x-6-10x³+13+x³=
(9x-4x)+(-4x³-10x³+x³)+(-6+13)=
5x-13x³+7
c)2x³+8x²-x²+15-8x³-4-9x²=
(2x³-8x³)+(8x²-x²-9x²)+(15-4)=
-6x³-2x²+11
d)5x²+14+6x³-3x²-5-7x³-8x²=
(5x²-3x²-8x²)+(14-5)+(6x³-7x³)=
-6x²+9-x³
e)-x²-8x³-3+16x²-x³-18+9x³=
(-x²+16x²)+(-8x³-x³+9x³)+(-3-18)=
15x²-21
f)-x³+2+5x²-17x³-8x²-10+3x=
(-x³-17x³)+(2-10)+(5x²-8x²+3x²)=
-18x³-8
