A right triangle with an angle of 45 degrees is an isosceles right triangle, which means that its other acute angle is also 45 degrees, and the two right-angled sides are equal. If the length of the right-angled side is 1, then the length of its hypotenuse is √2, so the ratio of the three sides is 1:1:√2

45 ̊ Rad π/4 Sine 0.707107 Cosine 0.707107 Tangent 1 Cotangent 1