Question

Ifsina=cosa,then the value of 2tana+cos2a is

Answer 1

==> sin a = cos a

==> sin a = sin (90 - a)

==> a = 90 - a

==> a = 45

now,

2 tan a + cos 2a

==> 2 tan 45 + cos 2×45

==> 2×1 + cos 90

==> 2 + 0

==> 2

Here, your answer is 2

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