Processing Math: Done

From Förberedande kurs i matematik 1

The right-hand side of the equation is a constant, so the equation is in fact a normal trigonometric equation of the type cosx=a.

In this case, we can see directly that one solution is x=6. Using the unit circle, it follows that x=2−6=116 is the only other solution between 0 and 2.

We obtain all solutions to the equation if we add multiples of 2 to the two solutions above,

x=6+2nandx=611+2n

where n is an arbitrary integer.