Question

Find angle x of 120 and 60 degrees
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Answer 1

Step-by-step explanation:

We know that cos 2 α+cos 2 β+cos 2 γ=1,i.e., sum of the squares of the direcction cosines is unity,Where α,β,γ are the angles made by a line with positive direction of the axes,⟹ 41+cos 2 β+ 41 =1⟹cos 2 β= 21 cosβ= 21 or − 21 ⟹β=45 0 or135 0