- #1

poiboi86

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Hi.

I'm solving the definite integral 4π∫{0,3/2}(x^3)dx

For some reason I get a different answer solving by hand and using my TI-89 than I do when I use an online calculator or my TI-36X Pro. I have to use the TI-36X Pro to take my Engineering FE exam in 2 & 1/2 weeks and need to know why I'm getting these different answers.

Does anyone see what I'm missing?

Solving by hand I get πx^4|{0,3/2} = π(3/2)^4 - 0 = 81π/16

This is also what the solution shows, and what my TI-89 calculator gives me as an answer.

But for some reason when I type that same integral into my TI-36X Pro calculator, or an online integral calculator like: <http://www.solvemymath.com/online_math_calculator/calculus/definite_integral/index.php>

I get the answer 15.904 which is 5π/16.

Thank you very much!

Isaac

## Homework Statement

I'm solving the definite integral 4π∫{0,3/2}(x^3)dx

For some reason I get a different answer solving by hand and using my TI-89 than I do when I use an online calculator or my TI-36X Pro. I have to use the TI-36X Pro to take my Engineering FE exam in 2 & 1/2 weeks and need to know why I'm getting these different answers.

Does anyone see what I'm missing?

## The Attempt at a Solution

Solving by hand I get πx^4|{0,3/2} = π(3/2)^4 - 0 = 81π/16

This is also what the solution shows, and what my TI-89 calculator gives me as an answer.

But for some reason when I type that same integral into my TI-36X Pro calculator, or an online integral calculator like: <http://www.solvemymath.com/online_math_calculator/calculus/definite_integral/index.php>

I get the answer 15.904 which is 5π/16.

Thank you very much!

Isaac

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