Question 128056: workbook problem i got very partial credit on... please explain/show how to solve...
(4a+1/a^2-4) - (3a-a+7/a^2-4) Answer by crzyy321(5) (Show Source):
The a just gets copied along.
The answer is a
a
4*a evaluates to 4a
Multiply the exponent of a by 2giving a^2
The answer is a^2
a^2 evaluates to a^2
To divide 1 by a^2
The a^2 just gets copied along in the denominator.
The answer is a^--2
1/a^2 evaluates to a^-2
4*a+1/a^2 evaluates to 4a+a^-2
The answer is 4a+a^-2-4
4*a+1/a^2-4 evaluates to 4a+a^-2-4
Multiply a and 3
Multiply a and 1
The a just gets copied along.
The answer is a
a
3*a evaluates to 3a
3*a-a evaluates to 2a
Multiply the exponent of a by 2giving a^2
The answer is a^2
a^2 evaluates to a^2
To divide 1 by a^2
The a^2 just gets copied along in the denominater
The answer is a^-2
7/a^2 evaluates to 7a^-2
3*a-a+7/a^2 evaluates to 2a+7a^-2
The answer is 2a+7a^-2-4
3*a-a+7/a^2-4 evaluates to 2a+7a^-2-4
To subtract the polynomials and we try to subtract terms in one polynomialwith any like terms in the other polynomial.
Be very careful with the "-" sign in front 2a+7a^-2-4 it is to be used on all terms in it.
4a - 2a = 2a
a^-2_7a^-2=-6a^-2
-4 - -4 = 0
The answer is 2a-6a^-2
(4*a+1/a^2-4)-(3*a-a+7/a^2-4) evaluates to 2a-6a^-2
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The final answer is 2a-6a^-2
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