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viva [34]
2 years ago
5

Prove the identity cos(A+B+C)=cosAcosBcosC-cosAsinBsinC-sinAcosBcosC-sinAsinBcosC

Mathematics
1 answer:
blagie [28]2 years ago
4 0
Hello !

cos (a+b) = cos a cos b - sin a sin b
sin (a+b) = sin a cos b + sin b cos a

cos (a+b+c) = cos (a+(b+c))
cos (a+b+c) = cos a cos (b+c) - sin a sin (b+c)
cos (a+b+c) = cos a (cos b cos c - sin b sin c) - sin a (sin b cos c + sin c cos b)
cos (a+b+c)=cos a cos b cos c - cos a sin b sin c - sin a sin b cos c - sin a cos b sin c
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Matthew has 2 dozen eggs. He uses 3/4 of the first dozen and 5/6 of the second dozen for baking.
madreJ [45]

Answer:

5 eggs.

Step-by-step explanation:

Well, 3/4 of 12 is 9 and 5/6 of 12 is 10. So, 12 - 9 = 3 and 12 - 10 = 2

Therefore, Matthew has 5 eggs left over.

I hope I helped ^^

7 0
3 years ago
What is the equation of the following line written in slope intercept form? (-5,-1)
solmaris [256]

Answer:

\large\boxed{y=-\dfrac{2}{3}x-\dfrac{13}{3}}

Step-by-step explanation:

The slope-intercept form of an equation of a line:

y=mx+b

m - slope

b - y-intercept

The formula of a slope:

m=\dfrac{y_2-y_1}{x_2-x_1}

From the graph we have two points (-5, -1) and (-2, -3).

<em>Look at the picture</em>.

Calculate the slope:

m=\dfrac{-3-(-1)}{-2-(-5)}=\dfrac{-2}{3}=-\dfrac{2}{3}

Put it to the equation in slope-intercept form:

y=-\dfrac{2}{3}x+b

We can't read the y-intercept from the graph. Therefore put the coordinates of the point (-5, -1) to the equation and calculate <em>b</em>:

-1=-\dfrac{2}{3}(-5)+b

-1=\dfrac{10}{3}+b         <em>subtract 10/3 from both sides</em>

-\dfrac{3}{3}-\dfrac{10}{3}=b\to b=-\dfrac{13}{3}

Finally:

y=-\dfrac{2}{3}x-\dfrac{13}{3}

4 0
3 years ago
What is the measurement of abd <br><br>​
belka [17]

Answer:

it is 23. always remember it's supposed to add up to 180. So add up all your numbers and subtract the total from 180 to get your answer

4 0
2 years ago
Read 2 more answers
How many times greater is the 4 in the thousands place compared to the 4 in the hundreds place?
lora16 [44]
It is 10 more in the thousands than the hundreds... multiply 100 x 10...
4 0
2 years ago
Write as a fraction or mixed number in simplest form. Show all work please
Gemiola [76]
First you gotta change it to a fraction, which would be 6/10 because it's in the tenths place. Now simplify it, which would be 3/5. 
4 0
2 years ago
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