Question

cot ( ^{-1} ). (Make biangle)
( left.theta=cot ^{-1} x quad frac{sqrt{1+x^{2}}}{x}right} )
( Rightarrow sin (Q) )
( Rightarrow frac{1}{sqrt{1+x^{2}}} )
( tan ^{-1} frac{1}{sqrt{1+x^{2}}} frac{sqrt{2+x^{2}}}{sqrt{1+x^{2}}} )
( cos theta_{1} )
( =frac{sqrt{1+x^{2}}}{sqrt{2+x^{2}}}=sqrt{frac{1+x^{2}}{2+x^{2}}}=operatorname{PHS} )
Flence Proved

# XII. Show that cos[ tan-'{sin (cotx)]]= 1** v 2+x² LL show that x+y+z = XYZ

Solution