Given the value of cos 25° ≈ 0.9063, enter the sine of a complementary angle. Use an expression relating trigonometric ratios of complementary angles.


cos 25° =___ ° ≈ ____

cos(x) = sin(90-x)

That's what the co- in cosine means: sine of the complement.

what do you mean i dont get it ..

what, you can't figure 90-25 ?

no like what i put in the boxes ..

im taking a practice test for next year lol im still in algebra 1 and have no knoledge in geometry yet

He did not understand my reply to the last question either. He clearly has not studied the material yet.

im not taking a geometry class yet .. im still in algebra 1

If you were taking geometry, you would be in serious trouble.

lol obviously.. i dont really understand any of this

To find the sine of the complementary angle, we can use the relationship between trigonometric ratios of complementary angles. The complementary angle of 25° is 90° - 25° = 65°.

The relationship between sine and cosine of complementary angles is:
sin θ = cos (90° - θ)

Therefore, to find sin 65°, we substitute θ = 65° in the above equation:
sin 65° = cos (90° - 65°)

cos (90° - 65°) can be simplified to cos 25°.

Given that cos 25° ≈ 0.9063, we can say that sin 65° ≈ 0.9063.