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tekilochka [14]
3 years ago
15

Prove that cos^3x+3cos2x= 4 (cos^6 x-sin^6x)

Mathematics
1 answer:
gavmur [86]3 years ago
5 0
But this isn't true... If x=\dfrac\pi2, you have

\cos^3\dfrac\pi2+3\cos\pi=0-3=-3
4\left(\cos^6\dfrac\pi2-\sin^6\dfrac\pi2\right)=4(0-1)=-4

but of course -3\neq-4.
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In Lixue’s garden, the green pepper plants grew 5 inches in 34 month. At this rate, how many feet can they grow in one month? (L
beks73 [17]

Answer:

<h2>0.15 inches per month</h2>

Step-by-step explanation:

step one:

This problem is focused on the growth rate of a plant.

given data

the plants grow 5 inches in 34 months

and also that 1 month= 4 weeks

step two:

We can still say that

if 34 months see a growth of 5 inches

then 1 months will be X inches

cross multiply we have

X= 5/32 inches

step three:

converting this number to decimal we have

X= 0.15 inches per month

Therefore the growth rate would be

0.15 inches per month

5 0
3 years ago
A tenant rented a store to use as a real estate school at a base rent of $1,500 a month. Additionally, the tenant agreed to pay
allsm [11]

Answer:

3. $600,000

Step-by-step explanation:

We have been given that a tenant rented a store to use as a real estate school at a base rent of $1,500 a month. Additionally, the tenant agreed to pay 3% of gross annual sales over $200,000.

Let us find base annual rent.

\text{Base annual rent}=\$1500\times 12\\\\ \text{Base annual rent}=\$18,000

Let us find the amount of rent paid as 3% of gross annual sales.

\$30,000-\$18,000=\$12,000

Let us find amount of sales over $200,000 by dividing $12000 by 3% or 0.03.

\frac{\$12,000}{0.03}=\$400,000

Total sales would be $400,000 plus $200,000.

\text{Total sales}=\$400,000+\$200,000\\\\ \text{Total sales}=\$600,000

Therefore, the total sales for that year was $600,000 and 3rd option is the correct choice.

7 0
4 years ago
Sales tax in Harris County is 7%. If the sales tax on a new car was $1400, what was the selling price of the car?
Dahasolnce [82]

Answer:

Bill of sale is not itemized or no sales tax has been paid to the state where the vehicle was purchased Sales tax is calculated using the following formula: (Vehicle Price – Trade in Value) x 6.25.

Step-by-step explanation:

3 0
3 years ago
-9/2+ 1/2 + 13/2 = -1/2 (8+13)
AysviL [449]

Answer:

−9

2

+

1

2

+

13

2

?

=

−1

2

(8+13)

2.5≠−10.5

False

Step-by-step explanation:

5 0
3 years ago
A bus trip takes 1.5 hours. By plane, the same trip takes 30 minutes. How
DENIUS [597]

Answer:

2 times faster

Step-by-step explanation:

because the plane takes one hour less than the bus and 60 min equal a hour and 30 plus 30 equal 60 which is a hour so then it would be 2 times as faster because it is 30 twice to equal the 60

4 0
3 years ago
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