SSC CGL 2024 PYQ — Question 55

SSC CGL - 09 Sep 2024 - Shift 3 • Quantitative Aptitude • Q55

If 7sinθ + 4cosθ9sinθ − 2cosθ=54{7sinθ\ +\ 4 cosθ \over 9sinθ\ -\ 2cosθ} = {5\over 4}, then the value of tan2θ + 5tan2θ − 5tan^2θ\ +\ 5 \over tan^2θ\ -\ 5 is:

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Correct answer: B

Explanation

The correct answer is Option 2 i.e. −2121769-{2121\over 769}.

7sinθ + 4cosθ9sinθ − 2cosθ=54{7sinθ\ +\ 4 cosθ \over 9sinθ\ -\ 2cosθ} = {5\over 4}

Dividing both sides by cosθ

⇒ 7sinθcosθ + 49sinθcosθ− 2=54{7{sinθ\over cos \theta}\ +\ 4 \over 9{sinθ\over cos\theta} -\ 2} = {5\over 4}

⇒ 7tanθ + 49tanθ− 2=54{7{tan \theta}\ +\ 4 \over 9{tan\theta} -\ 2} = {5\over 4}    [sinθ/cosθ = tanθ]

⇒ 4(7 tanθ + 4) = 5(9 tanθ -2)

⇒ 28 tanθ + 16 = 45 tanθ - 10

⇒ 17 tanθ = 26

⇒ tanθ = 26/17

Now,

The value of tan2θ + 5tan2θ − 5tan^2θ\ +\ 5 \over tan^2θ\ -\ 5 

⇒ (2617)2 + 5(2617)2− 5({26\over17})^2\ +\ 5 \over ({26\over17})^2 -\ 5

⇒ (676289) + 5(676289)− 5({676\over289})\ +\ 5 \over ({676\over289}) -\ 5

⇒ 676 + 1445676− 1445676\ +\ 1445 \over {676} -\ 1445 = −2121769-{2121\over 769}