SOLUTION: Perform the indicated operation. 3/2b - 5/3b^3

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Question 68798: Perform the indicated operation.
3/2b - 5/3b^3
Answer by rmromero(383) About Me  (Show Source):
You can put this solution on YOUR website!
Addition and Subtraction of Rational Expression must have the same denominator.
3%2F2b++-++5%2F3b%5E3

Since 2b and 3b^3 are not the same, we are going to find the LCD.

Let us get the prime factor for:
2b   = 2*  b
3b^3 =   3*b*b*b
LCD  = 2*3*b*b*b = 6b^3

Rewrite an equivalent expressions using the LCD.

%283%2A3b%5E2%29%2F6b%5E3++-++%285%2A2%29%2F6b%5E3

9b%5E2%2F6b%5E3+-+10%2F6b%5E3

Since the denominator are the same, you can subtract the expressions.
 
%289b%5E2+-+10%29%2F6b%5E3