Solve 2.5*cos(20)+2.5*cos(50)

$$2.5 \times \cos ( 20 ) +2.5 \times \cos ( 50 )$$

Evaluate

$$3.9562005761811195$$

Solution Steps

Evaluate trigonometric functions in the problem

$$2.5 \cdot 0.9396926207859084 + 2.5 \cdot 0.6427876096865394$$

Multiply 2.5 and 0.9396926207859084 to get 2.349231551964771.

$$2.349231551964771+2.5\times 0.6427876096865394$$

Multiply 2.5 and 0.6427876096865394 to get 1.6069690242163485.

$$2.349231551964771+1.6069690242163485$$

Add 2.349231551964771 and 1.6069690242163485 to get 3.9562005761811195.

$$3.9562005761811195$$

Factor

$$\frac{3 \cdot 13 \cdot 202882080829801}{2 ^ {16} \cdot 5 ^ {15}} = 3\frac{1912401152362239}{2000000000000000} = 3.9562005761811196$$