1It's clearly visible that function f(x) has no criticaql points, so no maxima and minima at all points
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At what point does the function
f(x)=(ax+b)/(cx+d)
has no maxima or minima
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5 Answers
1
11Let's check the derivative.....
f'(x)=ad-bcD2
D stands for the denominator.....
since f'(x) ≠0.....coz that will obviously make f(x) a const. function, let us have f'(x)>0
That gives f(x1)>f(x2)
if x1>x2
So maxima should be at infinity.....but when x→∞, f'(x)→0, thus function becomes const = ac
Same argument when f'(x)<0......
1If ad≠bc,
at all points of the domain of definition of the function of the derivative retains its sign.
If bc=ad,
then the function is a constant.
Hence the answer.
