If sin θ = 1/4 and tan θ 0, what is the value of cos θ?

Question

If sin θ = 1/4 and tan θ > 0, what is the value of cos θ?

misty1212 · Answer

HI!!

misty1212 · Answer

draw a triangle, like this |dw:1439233810971:dw|

misty1212 · Answer

there is a picture of an angle where the sine is $\frac{1}{4}$ since the "opposite over adjacent" is $\frac{1}{4}$

misty1212 · Answer

i meant "opposite over hypotenuse"

misty1212 · Answer

what you need is the adjacent side, which you find via pythagoras 
let me know when you get it

itsmichelle29 · Answer

7

misty1212 · Answer

oh no not 7

misty1212 · Answer

use pythagoras 
$$a^2+b^2=c^2\
x^2+1^2=4^2\
x^2+1=16\
x^2=16-1=15$$ so 
$$x=\sqrt{15}$$

itsmichelle29 · Answer

okay is the answe root15 /4

itsmichelle29 · Answer

@misty1212

misty1212 · Answer

yes

misty1212 · Answer

oh no!

misty1212 · Answer

you want the tangent right? not the cosine

itsmichelle29 · Answer

can u help me with like two more plz

itsmichelle29 · Answer

the cos

misty1212 · Answer

oh ok then yes

misty1212 · Answer

and i will be happy to help with two more

itsmichelle29 · Answer

thanks

itsmichelle29 · Answer

What are the period and phase shift for f(x) = −4 tan(x − π)?

itsmichelle29 · Answer

i think its pi and pi

misty1212 · Answer

period of tangent is $\pi$ so yeah

misty1212 · Answer

phase shift is $\pi$ as well you are right

itsmichelle29 · Answer

thanks and

itsmichelle29 · Answer

Use the graph below to answer the question that follows:

cosine graph with points at 0, negative 1 and pi over 2, 3 and pi, negative 1

What are the amplitude, period, and midline of the function?

 Amplitude: 8; period: π; midline: y = 1
 Amplitude: 8; period: 2π; midline: y = 5
 Amplitude: 4; period: 2π; midline: y = 5
 Amplitude: 2; period: π; midline: y = 1

misty1212 · Answer

really need the graph for this one

itsmichelle29 · Answer

attachment

itsmichelle29 · Answer

okay =)

misty1212 · Answer

ok much better
got a guess?

misty1212 · Answer

only need to look at the amplitude to pick from your choices

itsmichelle29 · Answer

Amplitude: 8; period: π; midline: y = 1
 Amplitude: 8; period: 2π; midline: y = 5
 Amplitude: 4; period: 2π; midline: y = 5
 Amplitude: 2; period: π; midline: y = 1

itsmichelle29 · Answer

well i thought it was -1 but thats not a chose

misty1212 · Answer

from -1 to 3, that is from the lowest point to the highest, is a distance of 4 units
the amplitude is half of that i.e. 2

misty1212 · Answer

also you can see that the period is $\pi$ since it goes up, and back down to -1 from 0 to $\pi$

itsmichelle29 · Answer

Amplitude: 2; period: π; midline: y = 1 is that the answer

misty1212 · Answer

yup

itsmichelle29 · Answer

omg ur amazing thanks

misty1212 · Answer

lol thanks$$\color\magenta\heartsuit$$