While solving cos(120°), why should I take cos(180 - 60) and instead of cos(90 + 30)?
Answers
Answered by
0
Because 120 is in 2nd quadrant
Siddune:
i know that, but how does that help in deciding which value to choose ?
we use cos(180-60) because
cos(180-x)=-cosx
Answered by
1
U can take both but its easy take 180-60
sorry but cos(180 - 60) => -cos60 = -1/2, but cos(90 + 30) => -cos30 = -√3/2, so how are they similar ?
Similar questions