Cos 340 degrees =
a.-cos 20 degrees
b. cos 20 degrees
c. cos 160 degrees
Trigonometrical Ratios:
We have to find the value of the trigonometry ratio. To solve the value, we use the trigonometrical ratios of (90∘+θ),(90∘−θ),(180∘+θ)
to find the values.
cos(180∘+θ)=−cos(θ)cos(90∘+θ)=−sin(θ)sin(90∘−θ)=cos(θ)
(90∘+θ)
lies in II quadrant and in II quadrant sin is positive and cos is negative
(90∘−θ)
lies in I quadrant and in I quadrant sin and cos both are positive