If x^2 + 9/x^2 = 42, what is the value of x - 3/x	Choose the correct option.
A) 6	B) 25	C) 9	D) 5	E) 3
To find : x-3/x. Let it be t.   =&gt; x-3/x = t   =&gt; (x^2 + 9/x^2) - 2*x*3/x = t^2 (Squaring both sides).   =&gt; (42) - 2*3= 
<gadget id="calculator">(42) - 2*3</gadget>
<output>36</output>
36=&gt; t^2 = 36. Thus t=6 or t=-6.   6nswer 6
<result>A</result>
If x^2 + 9/x^2 = 42, what is the value of x - 3/x