75.2% of 130 what is the answer and work

If sinA=√3-1/2√2,then prove that cos2A=√3/2 prove that

Ivan

Answer:

$\boxed{\sf cos2A =\dfrac{\sqrt3}{2}}$

Step-by-step explanation:

Here we are given that the value of sinA is √3-1/2√2 , and we need to prove that the value of cos2A is √3/2 .

Given :-

• $\sf\implies sinA =\dfrac{\sqrt3-1}{2\sqrt2}$

To Prove :-

• $\sf\implies cos2A =\dfrac{\sqrt3}{2}$

Proof :-

We know that ,

$\sf\implies cos2A = 1 - 2sin^2A$

Therefore , here substituting the value of sinA , we have ,

$\sf\implies cos2A = 1 - 2\bigg( \dfrac{\sqrt3-1}{2\sqrt2}\bigg)^2$

Simplify the whole square ,

$\sf\implies cos2A = 1 -2\times \dfrac{ 3 +1-2\sqrt3}{8}$

Add the numbers in numerator ,

$\sf\implies cos2A = 1-2\times \dfrac{4-2\sqrt3}{8}$

Multiply it by 2 ,

$\sf\implies cos2A = 1 - \dfrac{ 4-2\sqrt3}{4}$

Take out 2 common from the numerator ,

$\sf\implies cos2A = 1-\dfrac{2(2-\sqrt3)}{4}$

Simplify ,

$\sf\implies cos2A = 1 -\dfrac{ 2-\sqrt3}{2}$

Subtract the numbers ,

$\sf\implies cos2A = \dfrac{ 2-2+\sqrt3}{2}$

Simplify,

$\sf\implies \boxed{\pink{\sf cos2A =\dfrac{\sqrt3}{2}} }$

Hence Proved !

8 0

3 years ago

I’ll give brainliest!!!!! Pls help ASAP

storchak [24]

Answer:

$\sqrt[4]{x^{7} }$

Step-by-step explanation:

this is the same concept basically as simplifying $\sqrt{x}$ into $x^{\frac{1}{2} }$ . You can see that the denominator is in front of the radical and that any numbers in the numerator are the power of the number underneath.

7 0

3 years ago

PLS HELP ME ASAP WITH 11!! (MUST SHOW WORK!!) + LOTS OF POINTS!! *best if u sent picture with work SHOWN!!* - will give brainlie

sammy [17]

She can travel 12 miles

5 0

3 years ago

Read 2 more answers

Help me out please!!!!

lapo4ka [179]

Answer:

8/17

Step-by-step explanation:

opposite = hypotenuse

opposite = 8

hypotenuse =17

7 0

3 years ago

Read 2 more answers

3/4 over 3 1/4 simplified is?

Sergio039 [100]

Answer:

Convert

3

1

4

to an improper fraction.

A mixed number is an addition of its whole and fractional parts.

3

+

1

4

−

1

3

4

Add

3

and

1

4

To write

3

as a fraction with a common denominator, multiply by

4

.

3

⋅

4

+

1

4

−

1

3

4

Combine

3

and

4

.

3

⋅

4

+

1

4

−

1

3

4

Combine the numerators over the common denominator.

3

⋅

4

+

1

4

−

1

3

4

Simplify the numerator.

Multiply

3

by

4

.

12

+

1

4

−

1

3

4

Add

12

and

1

.

13

4

−

1

3

4

Convert

1

3

4

to an improper fraction.

A mixed number is an addition of its whole and fractional parts.

13

4

−

(

1

+

3

4

)

Add

1

and

3

4

.

13

4

−

7

4

Combine the numerators over the common denominator.

13

−

7

4

Subtract

7

from

13

.

6

4

Cancel the common factor of

6

and

4

.

Factor

2

out of

6

.

2

(

3

)

4

Cancel the common factors.

Factor

2

out of

4

.

2

⋅

3

2

⋅

2

Cancel the common factor.

2

⋅

3

2

⋅

2

Rewrite the expression.

3

2

The result can be shown in multiple forms.

Exact Form:

3

2

Decimal Form:

1.5

Mixed Number Form:

1

2

Step-by-step explanation:

6 0

3 years ago