In a △ABC, if acos2⁡B2+bcos2⁡A2=3c2 then 

In a ABC, if acos2B2+bcos2A2=3c2 then 

  1. A

     a, b, c are in A.P. 

  2. B

    a ,c, b are in A.P.

  3. C

     a, b, c are in G.P. 

  4. D

     none of these 

    Register to Get Free Mock Test and Study Material

    +91

    Verify OTP Code (required)

    I agree to the terms and conditions and privacy policy.

    Solution:

    we have ,

    acos2B2+bcos2A2=3c2a(1+cosB)+b(1+cosA)=3ca+b+(acosB+bcosA)=3ca+b+c=3c [c=acosB+bcosA]a+b=2ca,c,b are in A.P. 

    Chat on WhatsApp Call Infinity Learn

      Register to Get Free Mock Test and Study Material

      +91

      Verify OTP Code (required)

      I agree to the terms and conditions and privacy policy.