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Without using tables, evaluate the following: cosec330° cos60° tan345° sin290° sec245° cot30°. - Mathematics

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प्रश्न

Without using tables, evaluate the following: cosec330° cos60° tan345° sin290° sec245° cot30°.

योग

उत्तर

cosec330° cos60° tan345° sin290° sec245° cot30°.

sin30° = `(1)/(2)`
cosec30° = 2

cos60° = `(1)/(2)`
sec60° = 2

cos45° = `(1)/sqrt(2)`
sec45° = `sqrt(2)`
tan45° = 1
sin90° = 1

tan30° = `(1)/sqrt(3)`
⇒ cot30° = `sqrt(3)`
cosec330° cos60° tan345° sin290° sec245° cot30°

= `(2)^3(1/2)(1)^3(1)^2(sqrt(2))^2(sqrt(3))`

= `8 xx (1)/(2) xx 2 xx sqrt(3)`
= `8sqrt(3)`.

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अध्याय 27: Trigonometrical Ratios of Standard Angles - Exercise 27.1

APPEARS IN

फ्रैंक Mathematics [English] Class 9 ICSE
अध्याय 27 Trigonometrical Ratios of Standard Angles
Exercise 27.1 | Q 1.08

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