what is the difference between increasing and strictly increasing function,decreasing and strictle decreasing plz explain with example
incg & decrg function
is an increasing or decreasing function in a certain interval if +ve or –ve respectively in that interval because the tangent will make an acute angle for increasing function and obtuse angle for decreasing function. Hence,
= (+) for increasing functions and (-) for decreasing functions.
Remember: for all,
· If is an increasing function then, .
· If is a strictly increasing function then, .
· If is an decreasing function then, .
· If is a strictly decreasing function then, if.
As a matter of fact we should say that, sin x is a strictly increasing function.
Thus, cos x is a strictly decreasing function.