I have a trig problem that i need help with. I have done a) & b) but not c) because i don't get it.(adsbygoogle = window.adsbygoogle || []).push({});

Solve the following for:

a) principle values of x

b) 0°≤x≥180°

c) all values of x

1. 2sin²x-1=0

my work:

1a. principle values of x

sinx(2sin)-1 = 0

sinx(2sin)=1

sinx=1

(2sin/2)=

sin=½

1b. 0°≤x≥180°

sin1/2=±√1-cosx/2

2sin²x-1=0

2sin²x=1

2sin(sinx)=1

2sin/2=1/2

sin=1/2

sin½= 30°,90°

1c. all values of x

?????

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# Homework Help: Trig principle values problem

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