0

Guest

Courses New

If in a triangle ABC a Cos*2(c/2)+cos*2(A/2)=3b/2 then the sides a,b,c are

If in a triangle ABC a Cos*2(c/2)+cos*2(A/2)=3b/2 then the sides a,b,c are

Grade:12th pass

1 Answers

ALL IN ONE
24 Points
4 years ago
we know cosC=2cos^2(C/2)-1
 
so, a(1+cosC)/2+c(1+cosA)/2=3b/2
 
a+acosC+c+ccosA=3b
 
a+c+(acosC+ccosA)=3b
 
Using By projection formula: (acosC+ccosA)=b
 
a+c+b=3b
 
a+c=2b
This shows that a,b,c are in A.P.
thank you. my name : ashu mehta (bupp), (sirsa)
 
 

Think You Can Provide A Better Answer ?

Provide a better Answer & Earn Cool Goodies See our forum point policy

Other Related Questions on Trigonometry

View all Questions »

ASK QUESTION

Get your questions answered by the expert for free

Answer and earn gift vouchers

Win Gift vouchers upto Rs 500/-

View courses by askIITians

Design classes One-on-One in your own way with Top IITians/Medical Professionals

Click Here Know More

Complete Self Study Package designed by Industry Leading Experts

Click Here Know More

Live 1-1 coding classes to unleash the Creator in your Child

Click Here Know More

a Complete All-in-One Study package Fully Loaded inside a Tablet!

Click Here Know More