trig
posted by SONU .
Find the smallest positive value of x(in degree) for which tan(x+100°)=tan(x+50°)*tanx*tan(x50°)

Try an approximate graphical solution and refine solution by iterations.
Here's a graphical solution (x is in radians)
http://imageshack.us/photo/myimages/853/1313249887.png/