Question 1038604
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If 2sin^2theta -cos^2theta=2 then theta=?
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{{{2sin^2(theta) -cos^2(theta)}}} = {{{2sin^2(theta) - (1-sin^2(theta))}}} = {{{3sin^2(theta) -1}}}.


Therefore, if {{{2sin^2(theta) -cos^2(theta)}}} = 2 then

{{{3sin^2(theta) -1}}} = {{{2}}}  --->

{{{3sin^2(theta)}}} = {{{3}}}  --->

{{{sin^2(theta)}}} = {{{1}}}  --->

{{{sin(theta)}}} = +/-{{{1}}}  --->

{{{theta}}} = {{{pi/2 + 2k*pi}}}  or  {{{theta}}} = {{{-pi/2 + 2k*pi}}}, k = 0, +/-1, +/-2, . . . 

<U>Answer</U>.  {{{theta}}} = {{{pi/2 + k*pi}}},  k = 0, +/-1, +/-2, . . . 
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