Question

Dados A= x2+3x+3; B=3x2- 2x-1; C= -x2-x+2 determine:
A) a+b-c
b)a-(b-c)
Me ajudem por favor! Preciso para hoje.

Answer 1

vamos lá...

$a)~~~ A+B-C= \\ \\ x^2+3x+3+3x^2-2x-1-(-x^2-x+2)= \\ \\ x^2+3x+3+3x^2-2x-1+x^2+x-2= \\ \\ x^2+3x^2+x^2+3x-2x+x+3-1-2= \\ \\ 5x^2+4x-2x+\not3-\not3= \\ \\ 5x^2+2x$

$b)~~A-(b-c)= \\ \\ x^2+3x+3-[3x^2-2x-1-(-x^2-x+2)]= \\ \\ x^2+3x+3-[3x^2-2x-1+x^2+x-2]= \\ \\ x^2+3x+3-[3x^2+x^2-2x+x-1-2]= \\ \\ x^2+3x+3-[4x^2-x-3]= \\ \\ x^2+3x+3-4x^2+x+3= \\ \\ x^2-4x^2+3x+x+3+3= \\ \\ -3x^2+4x+6$