Q8 of 99 Page 34

Let and Show that each one of f and g is one - one but (f + g) is not one - one.



Here in this range, the lines do not cut the curve in 2 equal valued points of y, therefore, the function f(x) = sinx is one - one.




in this range, the lines do not cut the curve in 2 equal valued points of y, therefore, the function f(x) = cosx is also one - one.


(f + g):[0,] →R = sinx + cosx



in this range the lines cut the curve in 2 equal valued points of y, therefore, the function f(x) = cosx + sinx is not one - one.


Hence,showed that each one of f and g is one - one but (f + g) is not one - one.


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