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3 years ago

Cos4x = 8 cos^4 x - 8 cos^2 x + 1Please help me prove! :D

1 answer:

3 0

From cos(2x) = 2cos^2(x) -1

cos(4x) = 2[cos(2x)]^2 -1
= 2[2cos(x) -1]^2 -1
= 2[4cos^2(x) - 4cos(x) + 1] -1
= 8cos^2(x) - 8cos(x) + 1

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. Waipio Rd in Honokaa, Hawaii, is one of the steepest roads in the world. It rises 450 ft over a horizontal distance of 1,000 f

Deffense [45]

Answer: 50%

Step-by-step explanation:

From the question, we're given the information that Waipio Rd in Honokaa, Hawaii, is one of the steepest roads in the world and that it rises 450 ft over a horizontal distance of 1,000 ft.

Therefore, the percentage grade of this hill will be calculated as the height over the length and this will be:

= 450/1000 × 100

= 45%

= 0.45

= 0.5 to nearest tenth

= 50% to nearest tenth.

8 0

3 years ago

Can you write nine proper fraction and nine improper fractions using 3, 5, and 8

ra1l [238]

5/3 8/3 8/5... I don’t think it is possible

6 0

3 years ago

Find the area and perimeter of the given rectangle.

gulaghasi [49]

Answer:

Area: 48 sq. units

Perim: 28 units

Step-by-step explanation:

The distance between (-4, 3) and (-4,-3) is 6. The distance between (-4,-3) and (4,-3) is 8. So, 6 x 8 is 48, and that is the area.

6, 6, 8, and 8 are the lengths, so add those up to find the perimeter and you get 28.

4 0

3 years ago

If you have a bag with 7 red 3 green 4 blue 11 orange marbles what is the probability the you would randomly draw an orange marb

Andreas93 [3]

Answer:

11/25

Step-by-step explanation:

# means number

probability = # of orange marbles / # of total possible outcomes

7(red) + 3(green) + 4(blue) + 11(orange) = total possible outcomes

total possible outcomes = 25

# of orange marbles = 11

11/25; the probabilty of randomling picking an orange marble is 11/25

4 0

2 years ago

Find the volume of the compound shape

Sphinxa [80]

<h3>Given:</h3>

Hemisphere
Cylinder

<h3>Volume of the hemisphere:</h3>

$v = \frac{2}{3} \pi {r}^{3}$

$v = \frac{2}{3} \times \pi \times {1.5}^{3}$

$v = 7.07 \: {cm}^{3}$

<h3>Volume of the cylinder:</h3>

$v = \pi {r}^{2} h$

$v = \pi \times {1.5}^{2} \times 4$

$v = 28.27 \: {cm}^{3}$

<h3>Total volume:</h3>

$v = 7.07 + 28.27$

$v = 35.34 \: {cm}^{3}$

Hence, the volume of the given compound shape is 35.34 cubic centimeters.

7 0

2 years ago

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