Find the sine cosine and tangent of a smaller, sharp rectangle with a side of 40 cm and a hypotenuse of 41 cm.

41 cm

Suppose that: hypotenuse AB = 41 cm, leg BC = 40 cm.Applying the Pythagorean theorem, we find the length of the other leg:

AB ^ 2 = BC ^ 2 + AC ^ 2;

AC ^ 2 = AB ^ 2 – BC ^ 2;

AC ^ 2 = 41 ^ 2 – 40 ^ 2 = 1681 – 1600 = 81;

AC = √81 = 9 cm.

The smaller acute angle of this triangle will be the angle ∠B, since it is it that lies opposite the larger leg.

The sinus is the ratio of the opposite leg to the hypotenuse:

sin B = AC / AB;

sin B = 9/41 = 0.2195.

Cosine is the ratio of the adjacent leg to the hypotenuse:

cos B = BC / AC;

cos B = 40/41 = 0.9756.

Tangent – the ratio of the opposite leg to the adjacent one:

tg B = AC / BC;

tg B = 9/40 = 0.225.

Answer: sin B = 0.2195; cos B = 0.9756; tg B = 0.225.