मराठी

The value of sin50° – sin70° + sin10° is equal to ______.

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प्रश्न

The value of sin50° – sin70° + sin10° is equal to ______.

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उत्तर

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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Values of Trigonometric Functions at Multiples and Submultiples of an Angle
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पाठ 3: Trigonometric Functions - Exercise [पृष्ठ ५७]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
पाठ 3 Trigonometric Functions
Exercise | Q 49 | पृष्ठ ५७

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