Using the Fundamental Theorm of Calculus II to evaluate indefinite integrals

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The discussion focuses on evaluating definite integrals using the Fundamental Theorem of Calculus. The integrals presented involve polynomial and trigonometric functions, as well as an exponential function. The initial solutions provided by the user were incorrect, prompting a request for assistance. After recalculating with a calculator, the user found different results for each integral. The conversation highlights the importance of correctly applying the theorem and verifying calculations for accuracy.
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Homework Statement



Evaluate the following definite integrals using the Fundamental Theorem of Calculus:

1. 1 \int 4 ( (5x2+7x+5)dx )

2. -5pi/6 \int 4pi/6 (−6sinx+7cosx) dx )

3. 2 \int 4 ( (e^-4x)/((e^(-4x))+7) dx )

If it's unclear, the number on the left is the lower bound of the integral and the number on the right is the upper bound of the integral, followed by the function.

Homework Equations



a \int b f(x) dx = F(b) - F(a)

The Attempt at a Solution



Here are my solutions:

1. 1157/6

2. (-6(cos(4pi/6))+7(-sin(4pi/6)))-(-6(cos(-5pi/6))+7(-sin(-5pi/6)))

3. (4-0.25(log(1+7e^16)))-(4-0.25(log(1+7e^8)))

--

It's saying they're all wrong. I can't seem to find where I went wrong. If you could please help me out. Thanks,
 
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I did no 1. and got 172.5 as the solution.
 
Thanks - I ended up using my calculator for the sake of this question and its:

1. 172.5

2. 11.75833

3. 0.000011977
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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