Find no of solutions:

cos x = x

one.Graphically u can find it.The graph of y=x and cos x will cut once.

no of solution=1

cd any1 pl tell me wat exactly is the solution of x=cos x .. imean the coordinates of the point where the intersect

consider the function f(x)=x-cos(x)

derivative of f(x)=1-sin(x) which is >=0 for all real x

=> f(x) is increasing for all real x.

f(c)<0 for some c<-1 & f(c)>0 for some c>1

=> f(x) intersects the number line at ONLY ONE point.

=>f(x)=0 has ONLY ONE solution.