Question #b3c1c

1 Answer
Apr 16, 2017

In degrees:

x = 150^@ + n(360^@)x=150+n(360) and x = 210^@ + n(360^@)x=210+n(360) where n in ZZ

In radians:

x = (5pi)/6 + n(2pi) and x = (7pi)/6 + n(2pi) where n in ZZ

Explanation:

Given: cos(x)=-(sqrt12)/4

Simplify the right side:

cos(x)=-(sqrt3)/2

This is known to occur in both the 2nd and 3rd quadrants

In degrees:

x = 150^@ + n(360^@) and x = 210^@ + n(360^@) where n in ZZ

In radians:

x = (5pi)/6 + n(2pi) and x = (7pi)/6 + n(2pi) where n in ZZ