I will use x instead of beta for easier typing
tanxsinx + cosx = secx
I usually try to express everything in terms of sines and cosines, so
LS = (sinx/cos)sinx + cosx
= sin^2x/cosx + cos^2 x/cosx
= (sin^2 x + cos^2 x)/cosx
= 1/cosx
= secx
= RS
Give the other two a try using the same concept
5. Prove: Tan beta sin beta + cos beta = sec beta
6. Prove: ( tan y cos^2 y + sin^2 y)/ (sin y) = cos y+sin y
7. Prove (1+tan theta)/(1-tan theta) = (sec^2+2tan theta) /(1-tan^2 theta)
1 answer
1 answer