How Do You Calculate the Area Between Three Curves?

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To calculate the area between the curves defined by the equations 2y=4sqrt(x), y=5, and 2y+2x=6, it's essential to first simplify the equations to y=2√x and y=3-x. A sketch of the curves helps identify the triangular region formed and the necessary limits for integration. The area can be computed using two integrals, but the limits need to be accurately determined, particularly for the intersection points. The correct setup involves integrating from -2 to 1 for the first integral and from 1 to the correct x-coordinate for the second integral.
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Find region between these 3 curves.
2y=4sqrt(x)
y=5
2y+2x=6

Not sure how to find limits or actually setup the intigration.. is it just (left-mid-right?) But no idea for limits..
 
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When in doubt, make a sketch of the three curves (actually, one curve and two lines) and see what drops out.
 
Hmm, I tried that and got a somewhat triangle, broke it up and got 2 integrals..
From -2 to 1
(5-(3-x))

From 1 to 6
5-2sqrt(x)

But it was wrong
 
Chas3down said:
Find region between these 3 curves.
2y=4sqrt(x)
y=5
2y+2x=6

Not sure how to find limits or actually setup the intigration.. is it just (left-mid-right?) But no idea for limits..
You should simplify the 1st and 3rd equations.
y = 2√x
y + x = 3

There's no point in leaving in those common factors.

Chas3down said:
Hmm, I tried that and got a somewhat triangle, broke it up and got 2 integrals..
From -2 to 1
(5-(3-x))

From 1 to 6
5-2sqrt(x)

But it was wrong
Yes. You have the x coordinates for two of the intersection points correct, but the square root function and the horizontal line don't intersect for x = 6.

Try again.
 
almost
From -2 to 1
(5-(3-x))

From 1 to (try again)
5-2sqrt(x)
$$\mathrm{Area}=\int_{-2}^1 \! (5-(3-x))\, \mathrm{d}x+\int_1^{\text{try again}} \! (5-2\sqrt{x}) \, \mathrm{d}x$$
 
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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