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Question
The value of sin50° – sin70° + sin10° is equal to ______.
Options
1
0
`1/2`
2
Solution
The value of sin50° – sin70° + sin10° is equal to 0.
Explanation:
Given expression is sin50° – sin70° + sin10°
(sin50° – sin70°) + sin10° = `2cos (50^circ + 70^circ)/2 . sin (50^circ - 70^circ)/2 + sin 10^circ`
= 2cos60°.(–sin10°) + sin10°
= `-2 xx 1/2 sin10^circ + sin10^circ`
= –sin10° + sin10°
= 0
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