Question

8) Sendo A=5x²+3x-14 e B=2x²+5x+11, determine:
a)A-B
b)B-A
c)2.(A+B)

Answer 1

a ) 5x²+3x-14 - (2x²+5x+11)
5x²+3x-14 -2x²-5x-11
5x² - 2x² + 3x -5x -14 - 11
3x² -2x -25

b) 2x²+5x+11 - (5x²+3x-14)
2x²+5x+11 -5x²-3x+14
2x²-5x² +5x -3x +11 + 14
-3x² +2× + 25

c) 2. (5x²+3x-14 + 2x²+5x+11)
2. ( 5x²+2x² +3x +5x -14 +11)
2. (7x² +8x -3)
14x² + 16x -6

Answer 2

Sendo A=5x²+3x-14 e B=2x²+5x+11, determine: 

a)A-B = 5x²+3x-14 - (2x²+5x+11) ==> 5x² + 3x - 14 - 2x² - 5x - 11

3x² - 2x - 25 
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b)B-A ==> 2x²+5x+11 - (5x²+3x-14) ==> 2x²+5x+11 - 5x² - 3x + 14

 - 3x² + 2x + 25  ou -1( 3x² - 2x - 25)

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c) 2.(A+B) = 2.(5x²+3x-14 +2x²+5x+11) 

2( 7x² + 8x - 3) ==> 14x² + 16x - 6