3 years ago

If sin theta =1/4, theta in quadrant II, find the exact value of cos[theta +pi/6]

1 answer:

6 0

Using cos addition formula:
use x for theta
cos(x+π/6)=cosx*cos(π/6)-sinx*sin(π/6)
sinx=1/4
cosx=√15/4
cos(π/6)=√3/2
sin(π/6)=1/2
cos(x+π/6)=(√15/4*√3/2)-(1/4*1/2)
cos(x+π/6)=(√45/8)-(1/8 )
cos(x+π/6)=(√45-1)/8)

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A recipe for rolls requires 3/4 cup of butter. Wanda wants to make ½ of the recipe. How many cups of butter should Wanda use to

e-lub [12.9K]

Hey There!

Here is your answer:

The proper answer to this question is "1/4".

Reason:

What you have to do is subtract 3/4 from 1/2 in order to get your answer:

3*1=3
4*1=4
-
1*2=2
2*2=4

3-2=1

=1/4

Also....

In order to make 1/2 of the recipe Wanda would have to use 1/4 cups of butter. 

(Hence): Have of 3/4 is 1/4.

Therefore the answer is 1/4

If you need anymore help feel free to ask me!

Hope this helps!

~Nonportrit

4 0

3 years ago

What does 81% 90% 80% and 34% average into 20 points

Alja [10]

Answer:

71.25%.

Step-by-step explanation:

To find the average, we can simply add up the percentages and divide by how many there are.

We can do this by:

$\frac{81 + 90 + 80 + 34}{4}$ = 71.25%