Question

1)cos56°cos26°+sin 56°×sin 26°sin
98°cos52°+sin52°cos98°.

2) в радианы
65° 97° 974° 1°​

Answer 1

1 задание

1) cos56°cos26°+sin56°sin26° = cos(56°-26°) = cos30° = $\frac{\sqrt{3}}{2}$

2) sin 98°cos 52°+sin 52°cos 98 = sin(98°+52°) = sin150°= 0,5

3) sing8°cos52° + sin52° cos8° =  sin(8°+52°) = sin 60°=  $\frac{\sqrt{3}}{2}$

2 задание

65° = $65*\frac{\pi }{180}=\frac{13\pi }{36}$

97° = $97*\frac{\pi }{180}=\frac{97\pi }{180}$

974° = $974*\frac{\pi }{180}=\frac{987\pi }{90}$

1° =  $1*\frac{\pi }{180}=\frac{\pi }{180}$