Question

How do you evaluate `Arctan (-3/4 )`?

Answer 1

Find `arctan (-3/4)`

Ans: `- 36^@87 and 143^@13`

Explanation:

Calculator --> `tan x = - 3/4 = - 0.75` --> arc `x = -36^@87`
Trig unit circle gives another arc x that has the same tan value:
`x = -36.87 + 180 = 143^@13`