Question

$hola \: mate$
___find the value of sin(-465°)​

Answer 1

Answer:

Required value of sin( - 456° ) is approximately - 0.96.

Step-by-step explanation:

= > sin( - 465° )

= > sin( - 360° - 105° )

= > sin{ - ( 360° + 105° ) }

= > - sin( 360° + 105° ) { sin( - A ) = - sinA }

= > - sin( 2π + 105° )

= > - sin( 105° ) { sin( 2π + A ) = sinA }

= > - sin( 90 + 15° )

= > - cos15° { sin( 90° + A ) = cosA }

= > - cos( 45° - 30° )

= > - cos45°cos30° - sin45°sin30° { cos( A - B ) = cosAcosB + sinAsinB }

= > - ( 1 / √2 )( √3 / 2 ) - ( 1 / √2 ) ( 1 / 2 )

= > - √3 / 2√2 - 1 / 2√2

= > - ( 1 + √3 ) / 2√2

Or, 0.96 ( approx )

Hence the required value of sin( - 465° ) is approximately - 0.96( approx ).