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Without using table, find the value of the following: tan 2 60 ° + 4 cos 2 45 ° + 3 sec 2 30 ° + 5 cos 90 ° cos e c 30 ° + sec 60 ° − cot 2 30 ° - Mathematics

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प्रश्न

Without using table, find the value of the following: `(tan^2 60° + 4cos^2 45° + 3sec^2 30° + 5cos90°)/(cosec30° + sec60° - cot^2 30°)`

योग

उत्तर

`(tan^2 60° + 4cos^2 45° + 3sec^2 30° + 5cos90°)/(cosec30° + sec60° - cot^2 30°)`

= `((sqrt(3))^2 + 4 xx (1/sqrt(2))^2 + 3 xx (2/sqrt(3))^2 + 5 xx 0)/(2 + 2 - (sqrt(3))^2`

= `(3 + 4 xx (1)/(2) + 3 xx (4)/(3) + 0)/(2 + 2 - 3)`

= `(3 + 2 + 4)/(4 - 3)`
= 9.

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अध्याय 27: Trigonometrical Ratios of Standard Angles - Exercise 27.1

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फ्रैंक Mathematics [English] Class 9 ICSE
अध्याय 27 Trigonometrical Ratios of Standard Angles
Exercise 27.1 | Q 2.4

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