SOLUTION: Given cos(alpha) = 6/7, 0 < alpha > pi/2, find the exact value of cos(alpha/2)
Algebra.Com
Question 812506: Given cos(alpha) = 6/7, 0 < alpha > pi/2, find the exact value of cos(alpha/2)
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Given cos(alpha) = 6/7, 0 < alpha > pi/2,
find the exact value of cos(alpha/2)
--------------
cos(a/2) = sqrt[(1+cos(a))/2]
======
Your Problem:
cos(a/2) = sqrt[(1+(6/7))/2] = sqrt[(13/7)/2] = sqrt(13/14)
=============================
Cheers,
Stan H.
RELATED QUESTIONS
tan alpha= 2 find the value of sin alpha / sin^3 alpha + cos^3... (answered by anandtiwar62@gmail.com)
if sin alpha = 1/ square root 5 , 0< alpha < pie by 2,. find the exact values of
a)... (answered by jsmallt9)
Given sin(alpha)=3/4 and 0 (answered by stanbon)
find the exact value of sin(alpha-beta) given that cos(alpha)=1/5, a is between... (answered by lwsshak3)
if sin alpha =2/3 for pi/2≤alpha≤pi and cos beta =-5/7 for... (answered by lwsshak3)
I need help with these questions! Thank you so much!
1. Express sec 0- sin0tan0 in terms (answered by rwm)
cos(2\alpha +(\pi )/(4))=3tan(2\alpha +(\pi... (answered by ikleyn,greenestamps)
Hi, i'm just not sure how to even start this problem? Thanks for the help!
Given... (answered by stanbon)
Find the exact value for sin(alpha-beta) if sin(alpha) = -5/13 and cos(beta) = -8/17 with (answered by ikleyn)