cos[tan^-1(-1) + cos^-1 (-4/5)
How would I find the exact value of this one?

Will FAN and MEDAL

Question

cos[tan^-1(-1) + cos^-1 (-4/5)
How would I find the exact value of this one?

Will FAN and MEDAL

unknownunknown · Answer

1.5 Remember ^-1 is the inverse arc function, and not the inverse (not 1/x).

unknownunknown · Answer

I made a mistake, the answer is 3.2

anonymous · Answer

How'd you get that? All I have is that tan inverse is -pi/4

alekos · Answer

Did you leave out a bracket?

alekos · Answer

It looks like the final answer is the cosine of an angle which can only be less than or equal to one

anonymous · Answer

There's a bracket at the end sorry @alekos

unknownunknown · Answer

See if you get -0.1414214

anonymous · Answer

how would I get cos inverse (-4/5) and is cos inverse -pi/4 .. 3pi/4

unknownunknown · Answer

Use the arc cos function.

anonymous · Answer

Whats the function

unknownunknown · Answer

Are you using a calculator or other software?

anonymous · Answer

I'm not allowed to use a calculator

anonymous · Answer

Start from inside out to find values if each trigo inverse. Use triangle way to find exact values :)