Question

сложить син альфа и кос альфа

Answer 1

$sin a+cos a=sqrt{2}*(frac{1}{sqrt{2}}*sin a+frac{1}{sqrt{2}}*cos a)=\\sqrt{2}*(sin acosfrac{pi}{4}+sinfrac{pi}{4}cos a)=sqrt{2}*sin(a+frac{pi}{4})$
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$sin a+ cos a=sqrt{2}*sin(a+frac{pi}{4})$

Answer 2

=√2×sin ( a +π   )    вот!!!!!!!            
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