Calc 2 Integration Area Problem

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The discussion focuses on solving a calculus problem involving the area between the curves y=3-x^2 and y=x+1. Participants highlight that the original attempt at integration is incorrect due to the limits and the order of integration. It is suggested that integrating with respect to x would simplify the problem. Additionally, drawing the region can help clarify the bounds for integration. The conversation emphasizes the importance of correctly identifying the limits and the orientation of the area being calculated.
Alexa
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Homework Statement


Please help me solve the calc problem pictured!

Homework Equations


y=3-x^2 and y=x+1

The Attempt at a Solution


My attempt is in one of the photos!
 

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Alexa said:

Homework Statement


Please help me solve the calc problem pictured!

Homework Equations


y=3-x^2 and y=x+1

The Attempt at a Solution


My attempt is in one of the photos!
Type the problem statement, and your solution. Your images are not readable on my devices, and so I am unable to help or give hints.

For more on this issue, see the post "Guidelines for students and helpers", by Vela.
 
The region R is bounded by y=3−x^2 and y=x+1.
The area of the region can be found by integrating: integral from 1 to 2 ______dy + integral from 2 to 3 ______dy
For the first blank I had (sqrt(3-y))-(y-1) and for the second I had (sqrt(3-y)-2)
These are both wrong according to the system
 
Alexa said:
The region R is bounded by y=3−x^2 and y=x+1.
The area of the region can be found by integrating: integral from 1 to 2 ______dy + integral from 2 to 3 ______dy
For the first blank I had (sqrt(3-y))-(y-1) and for the second I had (sqrt(3-y)-2)
These are both wrong according to the system

So, the problem statement is asking you to find the area the hard way; integrating with respect to ##x## would be a lot easier.

Anyway, to see the ##x##-limits in the ##y##-integrals, you should start by drawing a picture of your region. The first (vertically lower) region goes from a negative value of ##y## to a positive value, and for each such ##y##, from a smaller (sometimes negative, sometimes positive) value of ##x## to a larger value of ##x##---giving a positive ##x##-length. You have your first integral going from a large value of ##x## to a smaller one---giving a negative ##x##-length.

You seem to be assuming that ##x## must be positive, but that is not stated anywhere in the problem as you wrote it.
 
Alexa said:
The region R is bounded by y=3−x^2 and y=x+1.
The area of the region can be found by integrating: integral from 1 to 2 ______dy + integral from 2 to 3 ______dy
For the first blank I had (sqrt(3-y))-(y-1) and for the second I had (sqrt(3-y)-2)
These are both wrong according to the system
Could you explain to us how you came up with your attempt?
 
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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