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2 years ago

Sin8x=8sinxcosxcos2xcos4x proving trig identity?

1 answer:

7 0

sin 8 x = 2 sin 4x cos 4x =
= 2 * 2 sin 2x cos 2x cos 4 x =
= 4 * 2 sin x cos x cos 2x cos 4x =
= 8 sin x cos x cos 2x cos 4x ( correct )

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The following observations are on stopping distance (ft) of a particular truck at 20 mph under specified experi- mental conditio

zzz [600]

Answer:

see explaination

Step-by-step explanation:

Data : 32.1 , 30.6 , 31.4 , 30.4 , 31.0 , 31.9

Mean X-bar = 31.23

SD = 0.689

Null Hypothesis : Xbar = mu

Alternate Hypothesis : Xbar > mu

z = (Xbar - mu) / (SD/sqrt(n))

= (31.23 - 30 ) /(0.689/sqrt(6))

= 4.372

P-value = ~0

Since P-vale < 0.01 , we will reject null hypothesis.

The data suggest that true average stopping ditance exceeds the maximum.

i) SD = 0.65

mu = 31

z = (Xbar - mu) / (SD/sqrt(n))

= (31.23 - 31) /(0.65/sqrt(6))

= 0.867

P-value = 0.3859 Answer

ii) SD = 0.65

mu = 32

z = (Xbar - mu) / (SD/sqrt(n))

= (31.23 - 32) /(0.65/sqrt(6))

= -2.9

P-value = 0.0037 Answer

i) SD = 0.8

mu = 31

z = (Xbar - mu) / (SD/sqrt(n))

= (31.23 - 31) /(0.8/sqrt(6))

= 0.704

P-value = 0.4814 Answer

ii) SD = 0.8

mu = 32

z = (Xbar - mu) / (SD/sqrt(n))

= (31.23 - 32) /(0.8/sqrt(6))

= -2.357

P-value = 0.0184 Answer

The probabilities obtained in part c are comparatively higher than that of part b.

i) For alpha =0.01

z = (Xbar - mu) / (SD/sqrt(n))

=> -2.32 = (31.23 - 31) /(0.65/sqrt(n))

=> (0.65/sqrt(n)) = (31.23 - 31)/-2.32

=> sqrt(n) = (0.65*(-2.32)) / (31.23 - 31)

=> n = 43 Answer

ii) For beta =0.10

z = (Xbar - mu) / (SD/sqrt(n))

=> -1.28 = (31.23 - 31) /(0.65/sqrt(n))

=> (0.65/sqrt(n)) = (31.23 - 31)/-1.28

=> sqrt(n) = (0.65*(-1.28)) / (31.23 - 31)

=> n = 13 Answer

4 0

2 years ago

PLEASE HELP! Robin bought a four-scoop ice cream cone having a scoop each of vanilla, chocolate, strawberry, and cherry. In how

soldi70 [24.7K]

There are 3 choices for the bottom scoop. Then there are only 3 choices for the scoop above that (since one flavor has already been used), then 2 choices for the next scoop, and 1 choice for the final scoop. This gives a total of 18 <span>possible cones.

Hope this helps.
</span>

4 0

2 years ago

if you are adding two fractions that are both greater than 1/2 what must be true about the sum? Give three examples to support y

Sunny_sXe [5.5K]

Answer:

If you are adding to fractions that are both greater than 1/2, the sum will be greater than 1.

Step-by-step explanation: 1/2 + 1/2 =1

Since both fractions are greater, obviously the sum will too.

Examples: 2/3+3/4= 1 5/12 4/6+6/9= 1 1/3

Hope this helps

6 0

2 years ago

HURRY PLEASE When 5 and 6 are multiplied by the same factor, how do the ratios compare to the ratio 5:6? The ratios are equivale

erma4kov [3.2K]

Answer:

The ratios are equivalent.

Step-by-step explanation:

If you multiply both 5 and 6, the ratio stays the same.

5:6 = 10:12 = 15:18 = 20:24 etc.

You can try this by dividing the larger number by the smaller number. You'll always get 1.2 as the "relationship", or ratio, is preserved.

24/20 = 1.2

15/18 = 1.2

10/12 = 1.2

6/5 = 1.2

6 0

2 years ago

suppose you could make a single "lump sum" deposit of $3679, in an investment that provides an annual percentage rate(apr) of 4%

yaroslaw [1]

Answer:

$\$5,698.30$

Step-by-step explanation:

The compound interest formula is equal to

$A=P(1+\frac{r}{n})^{nt}$

where

A is the Final Investment Value (future value)

P is the Principal amount of money to be invested

r is the rate of interest in decimal

t is Number of Time Periods

n is the number of times interest is compounded per year

in this problem we have

$t=11\ years\\ P=\$3,679\\ r=4\%=4/100=0.04\\n=365$

substitute in the formula above

$A=3,670(1+\frac{0.04}{365})^{365*11}$

$A=\$5,698.30$

3 0

2 years ago