(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

1.

Express as a sum of riemann and write the integral to express the area of the trapezoid with vertex (0,0) , (1,3) , (3,3) , (5,0).

2.

find the intersection points limited by these equations y = xsquare -3x and y = -2x +3 = 0

3.

the trapezoid with vertex (0,0) , (0,2) , (3,2) and (5,0) spins arround the y axis . Express it as a Riemann sum and write the integral to express the volume of the solid.

2. Relevant equations

3. The attempt at a solution

My biggest problems in problem 1 is that I dont know how to express the area of the trapezoid as an integral or as a function how can it be?

I have looked for this in many math books but they dont mention this at all.

In problem 2 I need to find the intersection points . I tried seting the two equations equal and then solving for x . but it resulted in a quadratic equation and the results werent right.

I need help because I ll have a semestral exam tomorrow about this subject and I really need to master it as much as I can.

Thank s alot in advance for your time.

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# Homework Help: I really need some help with these Riemann sum problems

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