Answer:
[tex](a)\ Sum = x^3+8x^2-4x+9[/tex]
[tex](b)\ Sum =3x^3-7x^2+6x +16[/tex]
[tex](c)\ Sum = x^3-x^2+10x+6[/tex]
[tex](d)\ Sum = 3x^4 -3x^3+ 6x^2-x+2[/tex]
Step-by-step explanation:
Required
Sum of the polynomials
[tex](a)\ x^3+5x^2+2, 3x^2-4x+7[/tex]
[tex]Sum = x^3+5x^2+2+3x^2-4x+7[/tex]
Collect like terms
[tex]Sum = x^3+5x^2+3x^2-4x+2+7[/tex]
[tex]Sum = x^3+8x^2-4x+9[/tex]
[tex](b)\ 2x + 5x^3-2x^2+7, 9+4x-5x^2-2x^3[/tex]
[tex]Sum =2x + 5x^3-2x^2+7+ 9+4x-5x^2-2x^3[/tex]
Collect like terms
[tex]Sum =5x^3-2x^3-2x^2-5x^2+4x+2x +7+ 9[/tex]
[tex]Sum =3x^3-7x^2+6x +16[/tex]
[tex](c)\ 5x^3+2x^2+4, 2x^2+7x-5, 7-5x^2 +3x-4x^3[/tex]
[tex]Sum = 5x^3+2x^2+4+ 2x^2+7x-5+ 7-5x^2 +3x-4x^3[/tex]
Collect like terms
[tex]Sum = 5x^3-4x^3+2x^2+ 2x^2-5x^2+7x+3x-5+ 7 +4[/tex]
[tex]Sum = x^3-x^2+10x+6[/tex]
[tex](d)\ 2x^4-3x^2+4x^3-5, 9x^2-7x^3-2x^4, 7-x+3x^4[/tex]
[tex]Sum = 2x^4-3x^2+4x^3-5+ 9x^2-7x^3-2x^4+ 7-x+3x^4[/tex]
Collect like terms
[tex]Sum = 2x^4-2x^4+3x^4 +4x^3 -7x^3-3x^2+ 9x^2-x-5+ 7[/tex]
[tex]Sum = 3x^4 -3x^3+ 6x^2-x+2[/tex]