Question

the idendity of sin2A+cos2A=1

Answer 1

$\mathfrak \green{ hello \: friend \: here \: is \: your \: answer : } \\ {sin}^{2} \theta + {cos}^{2} \theta = 1 \\ (a + b) {}^{2} = {a}^{2} + {b}^{2} - 2ab$

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