Q38 of 268 Page 4

Find the value off the following:

cos (60° + θ) – sin (30° - θ)

cos (60° + θ) – sin (30° - θ)

= sin {90°-(60°+θ)} – sin (30° - θ) [∵ cos θ = sin (90° - θ)]


= sin ( 90° - 60°-θ) – sin (30° - θ)


= sin (30° - θ) - sin (30° - θ)


= 0


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