All categories

3 years ago

Trigonometry

Mathematics

2 answers:

inessss [21]3 years ago

7 0

Answer:

±√(11/18)

Step-by-step explanation:

sinx = 5/6

applying the trigonometric rule sin²x + cos²x = 1

so to get cos²x = 1- sin²x

sinx = 5/6

sin²x = (5/6)² = 25/36

1-sin²x = 1-25/36 = 36-25 /36 = 11/36

cos ²x = 11/36

cos x = ±√(11/36)

cos 2x = 2 x±√(11/36) = ±√(11/18)

Fiesta28 [93]3 years ago

5 0

Answer:

-7/18

Step-by-step explanation:

cos(2x) = 1 - 2sin²x

cos(2x) = 1 - 2(5/6)²

= 1 - 2(25/36)

= 1 - 25/18

= -7/18

You might be interested in

In survey 17/25 of the people surveyed have a cat. what percent of the people surveyed have a cat?

mestny [16]

Answer:

The percentage of the people surveyed that have a cat is 68%

Step-by-step explanation:

we know that

To find the percentage of the people surveyed that have a cat, multiply the given fraction by 100

$\frac{17}{25}*100=17*4=68\%$

7 0

4 years ago

A 26 ft long ramp is used to reach 10 ft up a wall. The ramp covers a horizontal distance of 24 ft. To make the ramp less steep,

Anika [276]

Answer:

The length of new ramp is 49.03 ft.

Step-by-step explanation:

It is given that 26 ft long ramp is used to reach 10 ft up a wall. The ramp covers a horizontal distance of 24 ft.

If the horizontal distance is doubled, then the horizontal distance is 48 ft. The height remains same. Therefore the height of ram is 10 ft.

Use pythagoras in new right angle triangle.

$hypotenuse^2=base^2+perpendicular^2$

$(AE)^2=(AD)^2+(ED)^2$

$(AE)^2=(48)^2+(10)^2$

$(AE)^2=2304+100$

$AE=\sqrt{2404}$

$AE=49.0306027\approx 49.03$

Therefore the length of new ramp is 49.03 ft.

7 0

3 years ago

Which numbers are a distance of 1.6 units from 3 on this number line?

asambeis [7]

Answer:

4.6 and 2.4

Step-by-step explanation:

each small tick mark represents 0.1 so you start at 3 and you count the tick marks until you are 16 tick marks away from 3 and thats your answer.

6 0

3 years ago

Read 2 more answers

Solve the following inequality. 3x - 4 > 11

vampirchik [111]

3x - 4 > 11

15 it’s not that hard

3 0

2 years ago

Read 2 more answers

20 POINTS! The answer is x=4 and x= -5, how should I word it, saying how he is wrong?

ipn [44]

Answer:

The student took the numbers for the factors 5, -4 for the zeros instead of solving the equation

The zeros are -5, 4

Step-by-step explanation:

x^2 +x - 20=0

What 2 number multiply to -20 and add to 1

5*-4 = -20

5+-4 = 1

(x+5)(x-4) =0

Using the zero product property

x+5 = 0 x-4 =0

x=-5 x=4

4 0

3 years ago

Read 2 more answers