Question

Sendo que A=(x²+4) B= (2X + 1 ) E C = (x+3)
Determine;......
a) A+B.........
b) B-A .......
c) A.B.......
d) C.B.......
e) A+B+C.......
f) A-B-C......

PLEASE EU REALMENTE PRECISO DE AJUDA

Answer 1

A = x² + 4          B = 2x + 1         C = x + 3

A + B = 
(x² + 4) + (2x + 1)
x² + 4 + 2x + 1 =
x² + 2x + 5
====================================================
B - A = 
(2x + 1) - (x² + 4) =
2x + 1 - x² - 4 =
- x² + 2x - 3
===================================================
A . B =
(x² + 4).(2x + 1) = 
2x³ + x² + 4x + 4 
========================================================
C . B =
(x + 3)(2x + !) =
2x² + x + 6x + 3 =
2x² + 7x + 3
========================================
A + B + C =
(x² + 4) + (2x + 1) + (x + 3) =
x² + 4 + 2x + 1 + x + 3 =
x² + 3x + 8
==================================================
A - B - C =
(x² + 4) - ( 2x + 2) - (x + 3)
x² + 4 - 2x - 2 - x + 3 =
x² - 3x + 5