Cos A = square root 21 divided by 5 and sin A = 2/5. What is the exact value of cos 2A?

Answers

Answer 1

Answer: $cos\alpha=(√(21))/(5);\ sin\alpha=(2)/(5)\n\n\ncos2\alpha=cos^2\alpha-sin^2\alpha\n\ncos^2\alpha=\left((√(21))/(5)\right)^2=(21)/(25)\n\nsin^2\alpha=\left((2)/(5)\right)^2=(4)/(25)\n\ncos2\alpha=(21)/(25)-(4)/(25)=(17)/(25)$

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If x = 3z and z=2y, then x=?
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Plz help with this problem

Answers

To fond the midpoint add each term to each other and divide by 2.

3+2 = 5

5/2

In 2-i, i can also be written as 1i

So now 8+1 = 9

9/2

The midpoint would be 5/2 + 9/2i

To fond the midpoint add each term to each other and divide by 2.

3+2 = 5

5/2

In 2-i, i can also be written as 1i

So now 8+1 = 9

9/2

The midpoint would be 5/2 + 9/2i

PLEASE HELP MEEE!!!!! GIVE YOU ANYTHING YOU WANT JUST GIVE ME THE ANSWER! well, i wouldn't give you everything but i will give you brainlest and points. that's really all you need correct? Which binomials are factors of x2−9x−36?

Select the two correct answers.

x + 9

x−3

x + 3

x−4

x + 4

x−12

x + 12

x−9

Answers

Answer:

Step-by-step explanation:

x²-9x -36 =(x+3) (x -12)

because

x² -12x +3x -36 =

x( x-12) +3( x-12)=

(x-12) (x+3)

(3.49*10^5)*(6.31*10^2)

Answers

349000*631
3.49*100000*6.31*100
(3.49*6.31)*(100000*100)
22.0219*10000000
Now the answer is:
220219000

I hope this helps!

Your answer is 220219000.

Hope this helps.

Using the numbers 2,3,5,8 to make an equation to equal 104

Answers

The resulting equation is $8[(5*3)-2]=104$

Equation :

We have to make an equation by using numbers 2,3,5,8 and equal to 104

Now set the given number in such order so that we can get 104.

$5*3*8-2*8=104\n\n8[(5*3)-2]=104$

The resulting equation is $8[(5*3)-2]=104$

Learn more about the equation of function here:

brainly.com/question/25841119

One correct answer is:

8(2×5 + 3) = 104.

Explanation:

We start with 104 and work backward.

104 is divisible by 8:
104/8 = 13.

This means we need to make 13 out of 2, 3 and 5.

13 = 10+3.

This leaves us 10 to make out of 2 and 5; 2*5 = 10, so we have:

8((2*5)+3) = 104.

Scott has $500 in the bank. He withdraws the same amount of money each week for 12 weeks, at which point he has $20 left in the bank. How much money did he withdraw each week?

Answers

Scott knew that the only chance we would have to answer this problem would be if he kept his money in a bank that pays no interest, so that's what he did. The bank simply stored his money in a mayonnaise jar under a tightly-guarded mattress, and he was allowed to come in and take some out of it each week.

He started with $500. He withdrew (500 - 20) = $480 in 12 weeks.

So he must have come in and picked up 480/12 = $40 each week.

P = a + (n - 1)b, for b

Answers

P = a + (n - 1)b Subtratc a from both sides
P - a = (n - 1)b Divide both sides by (n - 1)
$(P - a)/(n - 1)$ = b Switch the sides to make it easier to read
b = $(P - a)/(n - 1)$

The answer is b=P-a-(n+1) all you had to do was the a and the parenthesis from the b and put it on the other side

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