Question 896201
{{{ cos ( theta +pi/4 ) = sqrt(2) / 2 }}}
{{{ cos ( theta +pi/4 ) = 1 / sqrt(2) }}}
Let {{{ alpha = theta + pi/4 }}}, then
{{{ cos( alpha ) = 1/sqrt(2) }}}
{{{ alpha = pi/4 }}}
{{{ alpha = ( 5*pi )/4 }}}
{{{ alpha = theta + pi/4 }}}
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{{{ pi/4 = theta + pi/4 }}}
{{{ theta = 0 }}}
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{{{ ( 5*pi )/4 = theta + pi/4 }}}
{{{ theta = pi }}}
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Those are the 2 solutions for {{{ theta }}}