Processing Math: Done

From Förberedande kurs i matematik 1

If we consider the entire expression x+40 as an unknown, we have a basic trigonometric equation and can, with the aid of the unit circle, see that there are two solutions to the equation for 0x+40360 namely x+40=65 and the symmetric solution x+40=180−65=115.

It is then easy to set up the general solution by adding multiples of 360,

x+40=65+n360andx+40=115+n360

for all integers n, which gives

x=25+n360andx=75+n360.