Take a Test JARRET MILLER Mozilla Firefox mStudentPlayer Tes

Take a Test JARRET MILLER Mozilla Firefox m/Student/Player Test aspx?test 5062 yes https://www. mathxl.col UNO- Math 1116- College Trigonometry Stephen Andrus, Jr. Test: Test 4 (copy) This Question: 1 pt 10 of 10 (7 complete) Find the following product, and write the product in rectangular form. Using exact values. cos 90 i sin 90 50 cos 60 i sin 60 (4( COS 90 i Sin 90 COS 60° i sin 60°) ype your answer in the form a bi.) Enter your answer in the answer box. O Ask me anything JARRETT MILLER I 2/1/16 7:56 PM Submit Test This Test 10 pts possible 2/1/2016

Solution

4(cos 90 + isin90)5(cos 60 + isin60)

First we have to convert them in exponential form

r(cos theta + isin theta)= r*e^{i * theta}

4e^i*pi/2 * 5e^i*pi/3   = 20 e^{i(pi/2+ pi/3)} =20e^i5pi/6

20(cos 150 + i sin 150)