MHB Arrange t_1, t_2, t_3 and t_4 in decreasing order

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For the given angles where \(0<x<45^{\circ}\), the expressions \(t_1=(\tan x)^{\tan x}\), \(t_2=(\tan x)^{\cot x}\), \(t_3=(\cot x)^{\tan x}\), and \(t_4=(\cot x)^{\cot x}\) can be arranged in decreasing order. The correct order is \(t_2 > t_1 > t_3 > t_4\). This arrangement is based on the properties of the tangent and cotangent functions within the specified range. The discussion highlights the mathematical reasoning behind the ordering of these expressions. Overall, the participants successfully confirmed the correct arrangement.
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Let $0<x<45^{\circ}$. Arrange

$$t_1=(\tan x)^{\tan x}$$, $$t_2=(\tan x)^{\cot x}$$, $$t_3=(\cot x)^{\tan x}$$, and $$t_4=(\cot x)^{\cot x}$$

in decreasing order.
 
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If $0<x<45º$,
$$0<\tan x <1\text{ and }0<\tan x<\cot x,\text{ so }t_2=(\tan x)^{\cot x}<(\tan x)^{\tan x}=t_1$$
$$1<\cot x,\text{ so }t_3=(\cot x)^{\tan x}<(\cot x)^{\cot x}=t_4.$$
$$0<\tan x<\cot x,\text{ so }t_1=(\tan x)^{\tan x}<(\cot x)^{\tan x}=t_3.$$
We conclude, $t_2<t_1<t_3<t_4.$
 
Fernando Revilla said:
If $0<x<45º$,
$$0<\tan x <1\text{ and }0<\tan x<\cot x,\text{ so }t_2=(\tan x)^{\cot x}<(\tan x)^{\tan x}=t_1$$
$$1<\cot x,\text{ so }t_3=(\cot x)^{\tan x}<(\cot x)^{\cot x}=t_4.$$
$$0<\tan x<\cot x,\text{ so }t_1=(\tan x)^{\tan x}<(\cot x)^{\tan x}=t_3.$$
We conclude, $t_2<t_1<t_3<t_4.$

Thanks for participating, Fernando Revilla and you got it absolutely correct, of course! Well done!(Clapping):)
 
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