Use the sum formula for tangents:
tan(a+b)=(tan(a)+tan(b))/(1-tan(a)tan(b))
If 345deg = 300deg + 45deg find tan 345deg
2 answers
It will be the same as -tan 15.
They probably want you to use the formula
tan(x+y) = [tanx + tany]/[1 - tanx*tany]
tan 300 = -tan 60 = -sqrt3
tan 45 = 1
tan 345 = (1 - sqrt3)/[1 + sqrt3)
= (1 - sqrt3)^2/(1-3)
= (-1/2)(sqrt3 -1)^2 = -0.26795
They probably want you to use the formula
tan(x+y) = [tanx + tany]/[1 - tanx*tany]
tan 300 = -tan 60 = -sqrt3
tan 45 = 1
tan 345 = (1 - sqrt3)/[1 + sqrt3)
= (1 - sqrt3)^2/(1-3)
= (-1/2)(sqrt3 -1)^2 = -0.26795
1 answer