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If 3 cotA = 2, then find the value of 3(cosec⁡2A−1)(sec⁡2A−1).\sqrt{\frac{3(\cosec^2 A - 1)}{(\sec^2 A - 1)}}.(sec2A−1)3(cosec2A−1)​​.​
Question

If 3 cotA = 2, then find the value of 3(cosec2A1)(sec2A1).\sqrt{\frac{3(\cosec^2 A - 1)}{(\sec^2 A - 1)}}.

A.

239\frac{2\sqrt{3}}{9} \\​​

B.

233\frac{2\sqrt{3}}{3} \\​​

C.

439\frac{4\sqrt{3}}{9} \\​​

D.

433\frac{4\sqrt{3}}{3}

Correct option is C

Given: 

3cotA = 2 

To find; 3(cosec2A1)(sec2A1)\sqrt{\frac{3(\cosec^2 A - 1)}{(\sec^2 A - 1)}} 

Solution: 

cotA=3base2perpendicular\cot A = \frac{3\rightarrow base}{2\rightarrow perpendicular} 

Then ,  

Hypotenuse = (3)2+(2)2=13\sqrt{(3)^2 +(2)^2} = \sqrt{13}​​

Now using in expression;

3(cosec2A1)(sec2A1) =3((133)21)(1322)1 =3(49)94 =129×49 =439\sqrt{\frac{3(\cosec^2 A - 1)}{(\sec^2 A - 1)}} \\ \ \\ = \sqrt{\frac{3(({\frac{\sqrt{13}}{3})}^2 - 1)}{({\frac{\sqrt{13}}{2}}^2) - 1}} \\ \ \\ = \sqrt{ \frac{3(\frac{4}{9})}{\frac{9}{4}}} \\ \ \\ =\sqrt{\frac{12}{9}\times \frac{4}{9}} \\ \ \\ = \frac{4\sqrt3}{9}​​

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