Math Core

Unit 7 · Test

Unit 7 test: Polar and Parametric Equations

15 questions. Answer them all, then submit to see your score. Solutions unlock after you submit.

This test covers polar coordinates, polar equations and their graphs, complex numbers in polar form (including De Moivre's Theorem and roots), and parametric equations.

Question 1

Convert the polar point (6,7π4)(6, \tfrac{7\pi}{4}) to rectangular coordinates.

Enter a point like (2, -3)

Question 2

Write the rectangular point (−3,1)(-\sqrt{3}, 1) in polar form (r,θ)(r, \theta) with r>0r > 0 and 0≤θ<2π0 \le \theta < 2\pi.

Enter a point like (2, -3)

Question 3

Which polar point names the same point as (−5,π3)(-5, \tfrac{\pi}{3})?

Question 4

Find the exact distance between the polar points (4,π3)(4, \tfrac{\pi}{3}) and (6,π)(6, \pi).

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 5

How many petals does the rose r=5cos⁡(5θ)r = 5\cos(5\theta) have?

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 6

The polar equation r=−8cos⁡θr = -8\cos\theta is a circle. Find its center in rectangular coordinates.

Enter a point like (2, -3)

Question 7

Which best describes the graph of r=2+4cos⁡θr = 2 + 4\cos\theta?

Question 8

Convert the polar equation r=5sin⁡θ−2cos⁡θr = \dfrac{5}{\sin\theta - 2\cos\theta} to a rectangular equation. Solve for yy.

Enter an expression, e.g. 3x^2 - 2x + 1

Question 9

Find the argument θ\theta of z=−2−23 iz = -2 - 2\sqrt{3}\,i, with 0≤θ<2π0 \le \theta < 2\pi.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 10

Let z1=4(cos⁡2π3+isin⁡2π3)z_1 = 4\left(\cos\tfrac{2\pi}{3} + i\sin\tfrac{2\pi}{3}\right) and z2=2(cos⁡5π6+isin⁡5π6)z_2 = 2\left(\cos\tfrac{5\pi}{6} + i\sin\tfrac{5\pi}{6}\right). Write z1z2z_1 z_2 in the form a+bia + bi and enter (a,b)(a, b).

Enter a point like (2, -3)

Question 11

Use De Moivre's Theorem to evaluate (3+i)6\left(\sqrt{3} + i\right)^6.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 12

Which number is a fourth root of −16-16?

Question 13

Eliminate the parameter from x=t−1x = t - 1, y=t2+3y = t^2 + 3. Write yy as a function of xx.

Enter an expression, e.g. 3x^2 - 2x + 1

Question 14

The segment from (−3,4)(-3, 4) to (5,0)(5, 0) is parametrized by x=−3+8tx = -3 + 8t, y=4−4ty = 4 - 4t, 0≤t≤10 \le t \le 1. Find the point where t=34t = \tfrac{3}{4}.

Enter a point like (2, -3)

Question 15

A ball is thrown so that x=30tx = 30t and y=6+40t−16t2y = 6 + 40t - 16t^2, with distances in feet and tt in seconds. What is the ball's maximum height, in feet?

Enter a number. Fractions like 3/4 and sqrt(2) are OK.