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find the value of : 3sin2 30° + 2tan2 60° - 5cos2 45° - Mathematics

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प्रश्न

find the value of :

3sin2 30° + 2tan2 60° - 5cos2 45°

योग

उत्तर

3 sin2 30° + 2 tan2 60° – 5 cos2 45° 

= `3(1/2)^2 +2(sqrt3)^2 – 5(1/sqrt2)^2`

= `(3)/(4)+6 –(5)/(2)`

= `(3 + 24 – 10)/(4)`

= `4(1)/(4)`

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अध्याय 23: Trigonometrical Ratios of Standard Angles [Including Evaluation of an Expression Involving Trigonometric Ratios] - Exercise 23 (A) [पृष्ठ २९१]

APPEARS IN

सेलिना Concise Mathematics [English] Class 9 ICSE
अध्याय 23 Trigonometrical Ratios of Standard Angles [Including Evaluation of an Expression Involving Trigonometric Ratios]
Exercise 23 (A) | Q 2.3 | पृष्ठ २९१

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