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kondaur [170]
3 years ago
10

If cos2A=11/25, show that cosA=6/5√2​

Mathematics
1 answer:
Hatshy [7]3 years ago
7 0

Answer:

it is not I think...

Step-by-step explanation:

Using the identity

\cos(2a) = 2 \cos^2(a) - 1

We can solve:

2 \cos^2(a) - 1 = \frac{11}{25}

2 \cos^2(a) = \frac{36}{25}

\cos^2(a) = \frac{18}{25}

\cos(a) = \sqrt \frac{18}{25}

\cos(a) = \sqrt{ 2 \cdot \frac{3^2}{5^2} }= \frac35 \sqrt 2

So whoever asked the question forgot the factor 2!!!

Or did I miss anything??

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The triangles are congruent by SSS.
Marysya12 [62]

Answer:

a and d

Step-by-step explanation:

i took the test

8 0
3 years ago
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50 + 50 - 25 x 0 +2 + 2
yuradex [85]

Answer:

104

Step-by-step explanation:

Any expression multiplied by 0 equals 0

when adding or subtracting 0, the quantity doesn't change

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3 years ago
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My teacher wouldn't help me.. and this is my last question. I need to know how to find the perimeter of the geometric figure (it
nika2105 [10]
This isn't really a geometry problem.  It's just an addition of fractions.

You know that 'perimeter' means 'the distance all the way around'.
And you know the length of all the sides of the parallelogram.
All you need to do is add them up !

(13/12) + (3/13) + (13/12) + (3/13) = the perimeter

Notice that two of the sides are equal, and the other two sides are also equal.
So you can make the job a little easier if you add up the twelfths first

(13/12) + (13/12) = 26/12

and then add up the thirteenths ...

(3/13) + (3/13) = 6/13 .

Now, the perimeter looks a little bit less complicated.
It's just
                   (26/12) + (6/13) = the perimeter.

This is the tough part.  Before you can add fractions, they need to have
a common denominator. 

The smallest common denominator for 12ths and 13ths is  <em>156 </em>!
Change each fraction to (<em>something over 156</em>), and add um up.
I'll leave that part to you.


5 0
4 years ago
U need question problem 2 to solve problem 3
Sergio [31]

Answer:

You are correct

Step-by-step explanation:

Start with 1 1/2. This can be made into an improper fraction which is 3/2

Now multiply both top and bottom of 3/2 by 5

(3*5)/(2 * 5) = 15 / 10

16/10 is just slightly bigger than 15/10

3 0
3 years ago
Read 2 more answers
Find the range of the following piecewise function.
Anna11 [10]

Given:

The piecewise function is

f(x)=\begin{cases}x+4 & \text{ if } -4\leq x

To find:

The range of given piecewise function.

Solution:

Range is the set of output values.

Both functions f(x)=x+4 and f(x)=2x-1 as linear functions.

Starting value of f(x)=x+4 is at x=-4 and end value is at x=3.

Starting value: f(-4)=-4+4=0

End value: f(3)=3+4=7

Starting value of f(x)=2x-1 is at x=3 and end value is at x=6.

Starting value: f(3)=2(3)-1=5

End value: f(6)=2(6)-1=11

Least range value is 0 at x=-4 and 0 is included in the range because -4 is included in the domain.

Largest range value is 11 at x=6 and 11 is not included in the range because 6 is not included in the domain.

So, the range of the given piecewise function is [0,11).

Therefore, the correct option is A.

5 0
3 years ago
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