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# If is an acute angle and $tan \theta + \cot \theta = 2 \tan \theta + \cot \theta = 2$, then the value of $\tan^{25} \theta +\cot^{ 25} \theta$ is

$\begin{array}{1 1}(A) \;2 \\(B)\;0 \\(C)\;none\;of\;these \\(D)\; 1 \end{array}$

Given: $tan \theta+cot \theta =2$
$\tan \theta + \large\frac{1}{\tan \theta }$$=2 \tan ^2 \theta+1= 2 \tan \theta \tan ^2 \theta -2 \tan \theta +1=0 \tan \theta -1=0 \tan \theta =1 and \cot \theta = \large\frac{1}{\tan \theta }$$=\frac{1}{1}$
$\tan ^{25} \theta+ \cot ^{25} \theta = (\tan \theta)^{25} +(\cot \theta )^{25}$
$\qquad= (1)^{25} +(1)^{25}$$=1+1=2$