find a

f(x)= ax + cosx is bijective
then a belongs to?
a) R⁺
b) R
c) R^-
d) R-(-1,1)

2 Answers

bijective means that the derivative should never be 0..
or even if it is.. it should always be either positive or negative..

got the hint?

k...
so ans will be d.
thnx. :)

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