Question

Evaluate sin (50°+θ)-cos (40°-θ)+ tan 1° tan 10° tan 20° tan 70° tan 80° tan 89°
plz answer.plz but don't wrong

Answer 1

Hope it helps u definitely
And thanks for asking doubt
Hope you understand

Answer 2

$\sin( \alpha + \beta ) = \sin\alpha \cos \beta + \cos\alpha \sin\beta$
$\cos( \alpha - \beta ) = \cos \alpha \cos \beta + \sin\alpha \sin \beta$