Solve cos^2(67.5)-sin^2(67.5)

$$\cos ^ { 2 } ( 67.5 ) - \sin ^ { 2 } ( 67.5 )$$

Evaluate

$$-0.7071067811865473684367105383256644$$

Solution Steps

Evaluate trigonometric functions in the problem

$$0.38268343236508984 ^ {2} - 0.9238795325112867 ^ {2}$$

Calculate 0.38268343236508984 to the power of 2 and get 0.1464466094067262900523523512712256.

$$0.1464466094067262900523523512712256-0.9238795325112867^{2}$$

Calculate 0.9238795325112867 to the power of 2 and get 0.85355339059327365848906288959689.

$$0.1464466094067262900523523512712256-0.85355339059327365848906288959689$$

Subtract 0.85355339059327365848906288959689 from 0.1464466094067262900523523512712256 to get -0.7071067811865473684367105383256644.

$$-0.7071067811865473684367105383256644$$