Binoy kumar mahato
Popular questions and responses by Binoy kumar mahato
math
ifcosX+cosY=a and sinX+sinY=b than prove thatsin2X+sin2Y=2ab(12/(a^2+b^2)
asked on October 4, 2017 
math
if cos(BC)+cos(CA)+cos(AB)=3/2 then prove that cosA+cosB+cosC=O and sinA+sinB+sinC=O after that prove that cos(BC)=cos(CA)=cos(AB)=1/2
asked on October 6, 2017 
math (trigonometry)
if tan A/2 =cosecAsin A then prove cos^2 A/2=cos 36 degree
asked on October 24, 2017 
math (trigonometry)
A=170 degree then prove that Tan A/2=1rot(1+Tan^2 A)/Tan A
asked on October 23, 2017 
math
limit x tends to infinity ( 1+root n)/(1rootn)
asked on December 3, 2017 
math
cos(AB)+cos(BC)+cos(CA)=3/2 then prove that cos A+cos B+cos C=0 and sin A+sin B+sin C=0 and also prove that cos(AB)=cos(BC)=cos(CA)=1/2
asked on October 7, 2017

maths (trigonometry)
L.H.S= cos 70/sin 70+4 cos 70 = cos 70+4 cos 70 sin 70/sin 70 =cos 70+2 sin 40/sin 70 = cos 70+2 cos 50/sin 70 = cos 70+cos 50+cos 50/sin 70 = 2 cos 60 cos 10+cos 50/sin 70 = cos 10+cos 50/sin 70 = 2 cos 30 cos 20 /cos 20 = root 3
posted on October 8, 2017