Question 1203778
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Be careful about tutor @MathLover1's notation.


{{{ j(x)=tan(pi/4x)}}} is <font color=red>not</font> the same as {{{ j(x)=tan(expr(pi/4)x)}}}


It appears she meant to use the second version. 


Here's a graph comparing the two functions
<a href="https://www.desmos.com/calculator/km7dhfq5h9">https://www.desmos.com/calculator/km7dhfq5h9</a>
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