
Andrew M. answered 12/15/15
Tutor
New to Wyzant
Mathematics - Algebra a Specialty / F.I.T. Grad - B.S. w/Honors
-(x2-1)-(x2-x-1)
Distribute the negative through
the parenthesis
= -x2+1-x2+x+1
Combine like terms
= -2x2+x+2
b. -x3(x+1) + x5(x2+x)
= -x3(x)-x3(1)+x5(x2)+x5(x)
= -x4-x3+x7+x6
There are no like terms since all the
exponents are different. Put in order
from highest to lowest power.
= x7+x6-x4-x3
c. -x4(1-x4) + x8(1-x8)
= -x4(1) -x4(-x4) + x8(1) + x8(-x8)
= -x4 + x8 + x8 - x16
Combine like terms and put in
descending order of power
= -x16+2x8-x4
d. -(x+5)(x2+1)
= -[x(x2) + x(1) + 5(x2 ) +5(1)]
= -(x3 + x + 5x2 + 5)
= -(x3 + 5x2 + x + 5)
= -x3 - 5x2 - x - 5

Andrew M.
Actually the minus sign in front of the parenthesis
is a negative sign...
The - in front of the parenthesis means the
terms inside the parenthesis are being multiplied
by -1.
It is understood that -(a+b) = -1(a+b) = -a-b
Just as -a means we have -1a
-a = -1a
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12/15/15

Andrew M.
So, no, the answer as given is correct.
Understand?
Report
12/15/15
Cortnee P.
12/15/15