Solve #cos2A=sqrt(2)(cosA-sinA)#?
2 Answers
Oct 21, 2017
See the answer below...
Explanation:
#cos2A=sqrt2(cosA-sinA)#
#=>cos2A(cosA+sinA)=sqrt2(cos^2A-sin^2A)#
#=>cos2A(cosA+sinA)=sqrt2 cdot cos2A#
#=>cancel(cos2A)(cosA+sinA)=sqrt2 cdot cancel(cos2A#
#=>(cosA+sinA)=sqrt2#
#=>sin^2A+cos^2A+2sinAcosA=2# [squared both side]
#=>1+sin2A=2#
#=>sin2A=1=sin90^@#
#=>2A=90^@#
#=>A=45^@# HOPE THE ANSWER HELPS...
THANK YOU...
Nov 9, 2017
When