Solve 2cos^240^circ-sin10^circ

$$2 \cos ^ { 2 } 40 ^ { \circ } - \sin 10 ^ { \circ }$$

Evaluate

$$0.999999999999999910985327528968$$

Solution Steps

Evaluate trigonometric functions in the problem

$$2 \cdot 0.766044443118978 ^ {2} - 0.17364817766693033$$

Calculate 0.766044443118978 to the power of 2 and get 0.586824088833465120492663764484.

$$2\times 0.586824088833465120492663764484-0.17364817766693033$$

Multiply 2 and 0.586824088833465120492663764484 to get 1.173648177666930240985327528968.

$$1.173648177666930240985327528968-0.17364817766693033$$

Subtract 0.17364817766693033 from 1.173648177666930240985327528968 to get 0.999999999999999910985327528968.

$$0.999999999999999910985327528968$$