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Without using table, find the value of the following: sin30°-sin90°+ 2cos0°tan30°tan60° - Mathematics

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Question

Without using table, find the value of the following:

`(sin30° - sin90° +  2cos0°)/(tan30° tan60°)` 

Sum

Solution

`(sin30° - sin90° +  2cos0°)/(tan30° tan60°)`

= `(1/2 - 1 + 2 xx 1)/(1/sqrt(3) xx sqrt(3))`

= `(1/2 - 1 + 2)/(1)`

= `(1)/(2) - 1 + 2`

= `(1)/(2) + 1`

= `(3)/(2)`

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Chapter 27: Trigonometrical Ratios of Standard Angles - Exercise 27.1

APPEARS IN

Frank Mathematics [English] Class 9 ICSE
Chapter 27 Trigonometrical Ratios of Standard Angles
Exercise 27.1 | Q 2.1

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