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1.Find the slope of the curve r = cos(2theta ) at theta =pi/6 ..................

ID: 2847525 • Letter: 1

Question

1.Find the slope of the curve r=cos(2theta) at theta =pi/6

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2. If x=2t-1 and y=3-4t^2, then dy/dx is

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3.Write the equation for the line tangent to the curve defined by F(t) = (t2 +1, 2t ) at the point where y=4.

A. y-4=ln2(x-2)

B. y-4=4ln2(x-2)

C. y-4= 4(x-5)

D. y-4=ln2(x-5)

E. y-4=4ln2(x-5)

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4. Sketch the curves (t^2, -2t+1) and (sin(t), cos(t)). The curves

A. do not intersect

B. intersect exactly once

C. intersect exactly twice

D. intersect three times

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5. Sketch the curves (t + 3, -2t+ 1) and (sin(t), cos(t)). The curves

A. do not intersect

B. intersect exactly once

C. intersect exactly twice

D. intersect three times

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6. Give the point of intersection of the curves (t + 3, -2t + 1) and (-3t + 1, 3t -4)

A. (7/2,0)

B. (10,10)

C. (10,-13)

D. (4,-1)

Explanation / Answer

1.) r' = -2 sin (2 theta)

at theta = pi/6

we get

slope = r' = -2 sin(2pi/6)

             = -2 sin(pi/3)

                = -sqrt 3

slope = -1.732


2.) dy/dt = -8t

dx/dt = 2

dy/dx = dy/dt * dt/dx = -4t