hamburger menu
All Coursesall course arrow
adda247
reward-icon
adda247
    arrow
    arrow
    arrow
    Find the value of sin⁡268∘+sin⁡222∘2(cos⁡217∘+cos⁡273∘)\frac{\sin^2{68^\circ} + \sin^2{22^\circ}}{2 \left( \cos^2{17^\circ} + \cos^2{73^\circ} \r
    Question

    Find the value of sin268+sin2222(cos217+cos273)\frac{\sin^2{68^\circ} + \sin^2{22^\circ}}{2 \left( \cos^2{17^\circ} + \cos^2{73^\circ} \right)}.

    A.

    –1

    B.

    0

    C.

    1

    D.

    12\frac{1}{2}

    Correct option is D

    Given: 

    sin268+sin2222(cos217+cos273)\frac{\sin^2{68^\circ} + \sin^2{22^\circ}}{2 \left( \cos^2{17^\circ} + \cos^2{73^\circ} \right)} 

    Formula Used: ​

    sin(90θ)=cosθ cos(90θ)=sinθ sin2θ+cos2θ=1\sin(90 -\theta) = \cos \theta\\ \ \\ \cos(90 -\theta) = \sin \theta \\ \ \\ \sin^2\theta +\cos^2\theta = 1

    Solution:

    sin268+sin2222(cos217+cos273) =sin268+sin2(9068)2[cos2(9073)+cos273] =sin268+cos2682[sin273+cos273] =12\frac{\sin^2{68^\circ} + \sin^2{22^\circ}}{2 \left( \cos^2{17^\circ} + \cos^2{73^\circ} \right)}\\ \ \\ = \frac{\sin^2{68^\circ} + \sin^2{(90 -68)^\circ}}{2 \left[ \cos^2{(90-73)^\circ} + \cos^2{73^\circ} \right]} \\ \ \\ = \frac{\sin^2{68^\circ} + \cos^2{68^\circ}}{2 \left[ \sin^2{73^\circ} + \cos^2{73^\circ} \right]}\\ \ \\ = \frac{1}{2}​​

    Free Tests

    Free
    Must Attempt

    CBT-1 Full Mock Test 1

    languageIcon English
    • pdpQsnIcon100 Questions
    • pdpsheetsIcon100 Marks
    • timerIcon90 Mins
    languageIcon English
    Free
    Must Attempt

    RRB NTPC Graduate Level PYP (Held on 5 Jun 2025 S1)

    languageIcon English
    • pdpQsnIcon100 Questions
    • pdpsheetsIcon100 Marks
    • timerIcon90 Mins
    languageIcon English
    Free
    Must Attempt

    CBT-1 General Awareness Section Test 1

    languageIcon English
    • pdpQsnIcon40 Questions
    • pdpsheetsIcon30 Marks
    • timerIcon25 Mins
    languageIcon English
    test-prime-package

    Access ‘RRB NTPC’ Mock Tests with

    • 60000+ Mocks and Previous Year Papers
    • Unlimited Re-Attempts
    • Personalised Report Card
    • 500% Refund on Final Selection
    • Largest Community
    students-icon
    354k+ students have already unlocked exclusive benefits with Test Prime!
    Our Plans
    Monthsup-arrow