Question

The value of sin50∘−sin70∘+sin10∘ is

A) 1

B) 2

C) -1

D) 0

Answer 1

sin 50° -sin70°+sin10°=.766-.939+.173=0

Answer 2

➡HERE IS YOUR ANSWER⬇

♧♧SOLUTION♧♧

$sin50 - sin70 + sin10 \\ \\ = (2 \: cos \frac{50 + 70}{2} \: sin \frac{50 - 70}{2} ) + sin10 \\ \\ = 2 \: cos60 \: sin( - 10) + sin10 \\ \\ = - 2. \frac{1}{2} .sin10 + sin10 \\ \\ = - sin10 + sin10 \\ \\ = 0$

♧♧RULES♧♧

$sin \alpha - sin \beta \\ \\ = 2 \: cos \frac{ \alpha + \beta }{2} \: sin \frac{ \alpha - \beta }{2}$

$sin( - \alpha ) = - sin \alpha$

$cos60 = \frac{1}{2}$

⬆HOPE THIS HELPS⬅