Section Practice
ΒΆThese are practice problems for the tests. Solutions are in the next section. While we will not present these, I am happy to answer questions about them in class. ConicsComplete the square for the parabola, y=4x2β8x+7. Sketch the parabola, labeling the vertex, focus, and directrix. Compute the area of the region bounded by the parabola, the x-axis, the vertical line through the focus, and x=32.
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For the ellipse 3x2+2y2β12x+4y+2=0, find
its center, vertices, foci, and the extremities of the minor axis;
an equation of the tangent to the ellipse at (0,β1).
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For the ellipse x29+y24=1,
set up a definite integral to evaluate the length of the arc of the ellipse from (3,0) to (β3,0);
find an approximation of the arc length in part 1.
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For the hyperbola 9y2β4x2+16x+36yβ16=0,
find its center, vertices, foci, and equations of asymptotes;
draw a sketch of the hyperbola and its asymptotes.
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For each of the following equations, identify whether the curve is a parabola, circle, ellipse, or hyperbola by removing the xy term from the equation by rotation of the axes.
x2+2xy+y2β4x+4y=0
x2+2xy+y2+xβyβ1=0
24xyβ7y2β1=0
8x2β12xy+17y2+24xβ68yβ32=0
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Find dydx and d2ydx2 for each of the following parametric curves.
x=acos(t), y=bsin(t)
x=invsin(t), y=invtan(t)
x=teet, y=tln(t) Only compute dy/dx for this one.
Let C be the curve defined by x=sin(t)+t, y=cos(t)βt, t is in [βΟ2,Ο2]. Find an equation of the tangent to C at the point (0,1).
Suppose we have an object traveling in the plane with position at time t of x=6βt2 and y=t2+4. When is the object stopped? When is it moving left? Right? Rewrite the parametric equations as a function by eliminating time.
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Find the length:
x=etcos(t) and y=etsin(t) from t=1 to t=4
x=4cos3(t) and y=4sin3(t) from t=Ο/2 to t=Ο
Find the points of intersection of the curves C1 with parametric equations x=t+1, y=2t2 and C2 with parametric equations x=2t+1, y=2t2+7. (Actuarial Exam)
Let C be the curve defined by x=2t2+tβ1, y=t2β3t+1, β2<t<2. Find an equation of the tangent to C at the point (0,5). (Actuarial Exam)
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For each of the following problems, find a polar equation of the graph having the given equation in the rectangular coordinate system.
4xβ3y=7
xy=1
x3+y3=3xy
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For each of the following problems, find an equation in the rectangular coordinate system having the given polar equation.
r=21β3cos(ΞΈ)
r=3sin(ΞΈ)
r2=6cos(2ΞΈ)
r=5sec(ΞΈ)
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For each of the following problems, find the points of intersection of the graphs of the given pairs of polar curves.
r=4cos(2ΞΈ); r=2
r=1βcos(ΞΈ); r=cos(ΞΈ)
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For each of the following problems, find the area of the region enclosed by the graph of the given polar equation.
r=4+4cos(ΞΈ)
r=4βsin(ΞΈ)
r=2sin(3ΞΈ)
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For each of the following problems, find the area of the intersection of the region enclosed by the graphs of the two given polar equations.
r=4β2cos(ΞΈ); r=2
r=2sin(2ΞΈ); r=2cos(ΞΈ)
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For each of the following problems, find the area of the inner loop of the limacon.
r=1β2cos(ΞΈ)
r=3β4sin(ΞΈ)