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Solve the following equations:cos 2θ = 5+14 - Mathematics

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प्रश्न

Solve the following equations:
cos 2θ = `(sqrt(5) + 1)/4`

योग

उत्तर

We know cos 36° = `(sqrt(5) + 1)/4`, 36° = `pi/5`

cos 2θ = cos 36° = `cos (pi/5)`

The general solution is

2θ = `2"n"pi +- pi/5`, n ∈ Z

 θ = `"n"pi +- pi/10`, n ∈ Z

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 3: Trigonometry - Exercise 3.8 [पृष्ठ १३३]

APPEARS IN

सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
अध्याय 3 Trigonometry
Exercise 3.8 | Q 3. (x) | पृष्ठ १३३

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