Find one positive angle and one negative angle that are soterminal with the given angle

For 9π/2 into degrees I got 13π/2 for the positive and 5π/2 for the negative.

Comparing these answers to other peoples mine seems to not be correct. 

What am I doing wrong? Plz explain.

 Nov 29, 2018
edited by BLANK  Nov 29, 2018

Your answers seem correct, but maybe the question wants a negative angle? (ex. -3π/2 )

Also, this is one of those questions where there are infinite possible answers, so maybe other people just wrote down something different.

 Nov 29, 2018

To find a positive co-terminal angle...add 2pi to 9pi/ 2


So we have   2pi + 9pi/2  =  4pi/2 + 9pi/2  =  13pi/2


To find a negative co-terminal angle....subtract 6pi from 9/pi/2


So we have


9pi/2 - 6pi  =     9pi/2  - 12pi/2  = -3pi/2


You are correct HL.....infinite answers are possible...!!!!



cool cool cool

 Nov 29, 2018

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