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mojhsa [17]
2 years ago
9

If cosa=1/2(a+1/a), verify that. cos2a=1/2(a²+1/a²)​

Mathematics
1 answer:
Alborosie2 years ago
3 0

Answer:

see explanation

Step-by-step explanation:

using the identity

cos2a = 2cos²a - 1 , then

cos2a

= 2[ \frac{1}{2}(a  + \frac{1}{a}) ]² - 1

= 2 [ \frac{1}{4} (a² + \frac{1}{a^2} + 2) ] - 1

= \frac{1}{2} (a² + \frac{1}{a^2} ) + 1 - 1

= \frac{1}{2} (a² + \frac{1}{a^2} ) ← thus verified

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What’s the answer to this question?
steposvetlana [31]

Answer:

its x^4

Step-by-step explanation:

its x^4

5 0
3 years ago
What is the additive inverse of -2 + 8i?
tatuchka [14]

Answer:

2 - 8i

Step-by-step explanation:

The additive inverse of something is basically the opposite of it. Another way to say this is that when you add the additive inverse to -2 + 8i, it will equal 0.

<u>An example:</u>

The additive inverse of 7 is -7 because not only is it the opposite, but also when you add 7 and -7, it equals 0.

<u>To solve</u>

So all you need to do is find the opposite of -2 + 8i. You can write it as:

-(-2 + 8i)  With the negative in the front because we want to find the opposite.

This then equals:

2 - 8i

You can check your answer by adding -2 + 8i and 2 - 8i to see if it equals 0:

(-2 + 8i) + (2 - 8i)  →  and it does equal 0

<u>ANSWER:</u> 2 - 8i

Hope you understand and that this helps with your question! :)

8 0
3 years ago
Find the distance between the line 1.2x − 0.5y + 1.1=0 and the origin.
denpristay [2]

Answer:

The answer to your question is: d = 0.85 units

Step-by-step explanation:

Data

Line equation:  1.2 x − 0.5 y + 1.1 = 0        A = 1.2; B = -0.5; C = 1.1

Point (0, 0)                                                  x = 0; y = 0

Formula

d = | Ax + By + C | / √(A² + B²)

Process

d = |(1.2)(0) + (-0.5)(0) + 1.1 | / √ (1.2)² + (0.5)²

d = | 1.1 | / √ 1.44 + 0.25

d = 1.1 / √ 1.69

d = 1.1 / 1.3

d = 0.85 units

7 0
3 years ago
Handles-n-Things is a small enterprise company buying new carpet for their office room. The room is 15 ft. wide and 24 ft. long.
Helen [10]

Hey there!

To find the area, we multiply the length by the width! The carpet will cover the area of the room.

24×15=360

But, the carpeting is sold in square yards, not feet. There are three feet in a yard, which means that one yard is 1/3 feet. Since we have 360 square feet, we will divide it by three to get yards.

360/3=120

Therefore, the office would need 120 square yards of carpeting.

Have a wonderful day!

4 0
3 years ago
ANSWER #3 AND #4 FOR ME
Dafna11 [192]

Answer:

use the scan & solve that brainly has

8 0
3 years ago
Read 2 more answers
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