Convert the equation to polar form Use variables r and as n

Convert the equation to polar form. (Use variables r and ? as needed.)

1720 EXX C Response dep 15158991 Assignment submission For this assignment. you submit answers by question parts. The number of submissions remaining for each question part only changes if you submit or change the answer. Assignment scoring Your last submission is used for your score. 18. O -1 points SPreCalc7 8.1.050 My Notes Ask Your Teacher Convert the equation to polar form. Use variables r and e as needed.) Submit Answer Save Progress View Previous Question Question 18 of 24 View Next Question Home My Assignments Extension Requesf WebAssign® 4.0 1997-2016 Advanced Instructional Systems, Inc. Al rights reserved

Solution

(r*cos())^2 - (r*sin())^2 = 7 (because x = r*cos() and y = r*sin() )

So (r^2) * (cos^2() - sin^2()) = 7

But a basic trig identity states that cos(2a) = cos^2(a) - sin^2(a)

So now we have: r^2 * cos(2) = 7 and thus

cos(2) = (7/r^2)