Definite Integral Calculator Problem

[poiboi86]

Hi.

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

 

[Dick]

The first answer is correct. 81π/16=15.90431. 5π/16=0.98174. I don't think there is anything wrong the calculators.