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Without using tables, find the value of the following: 4 cot 2 30 ° + 1 sin 2 60 ° − cos 2 45 ° - Mathematics

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Question

Without using tables, find the value of the following: `(4)/(cot^2 30°) + (1)/(sin^2 60°) - cos^2 45°`

Sum
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Solution

`(4)/(cot^2 30°) + (1)/(sin^2 60°) - cos^2 45°`

= `(4)/(sqrt(3))^2 + 1/(sqrt3/2)^2 - (1/sqrt(2))^2`

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

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

= `(8 + 8 -3)/(6)`

= `(13)/(6)`.

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Chapter 27: Trigonometrical Ratios of Standard Angles - Exercise 27.1

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Frank Mathematics [English] Class 9 ICSE
Chapter 27 Trigonometrical Ratios of Standard Angles
Exercise 27.1 | Q 2.5
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