`sin(135^0 - 30^0) = sin 135^0* cos 30^0 - cos 135^0 * sin 30^0 `
(we know that
`= sin (90+45) * cos 30 - cos(90+45) *sin 30^0 `
`=cos 45^0 * cos 30 - (-sin 45^0) * sin 30^0`
`= 1/sqrt2 * sqrt3/2 +1/sqrt2 * 1/2 `
`= (sqrt3+1)/(2sqrt2) = 0.9661 `
lets check with direct values. `sin(105^0) = 0.9659 ~~ 0.966` ``
Next expression is
`sin(135^0) - sin (30^0) `
`sin(135^0) - sin (30^0) = sin(90^0 +45^0) - sin 30^0 `
` = cos 45^0 - sin30^0`
`= 0.2071`
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