New guy and programming problem

[Albert Chan]

I never knew trig function were used as logarithm !
Example: arccos/cos vs ln/exp

0.123 * 0.456
= cos(82.9347°) * cos(62.8707°)
= 1/2 (cos(82.9347° + 62.8707°) + cos(82.9347° - 62.8707°))
= 1/2 (cos(145.8054°) + cos(20.0640°))
= 0.05608822 ~ 0.056088

0.123 * 0.456
= exp(ln(0.123) + ln(0.456))
= exp(-2.09557 + -0.78526)
= exp(-2.88083)
= 0.05608819 ~ 0.056088

But, how can trig function used for division ?