What is arctan(−1)? Negative StartFraction 3 pi Over 4 EndFraction
Negative StartFraction pi Over 4 EndFraction
StartFraction pi Over 4 EndFraction
StartFraction 3 pi Over 4 EndFraction

-pi/4 and 3pi/4

Step-by-step explanation:

Whenever you're given an inverse trig function like this, think "tangent of what gives me -1?" There are multiple ways in which you can solve this; knowing how tangent work, guess checking sin/cos to get -1, or using a calculator. The only way tangent can be an integer is if the sine and cosine of the angle are equal.

The only spots on the pi circle where this happens is pi/4, 3pi/4, 5pi/4, and 7pi/4. Answers B and D are correct

d. bc = 12 and ef = 16

step-by-step explanation:

we are given that δabc : δdef such that .

also, it is given that

so, from the options, we need that .

a.

b.

c.  

d.

as, we can see that only option d gives the same ratio as i.e. .

hence, the possible lengths are bc = 12 and ef = 16.

160

step-by-step explanation:

idk

i hope i