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3 years ago

(6y^2-9y+4)-(-7y^2+5y+1)

Mathematics

1 answer:

Vladimir79 [104]3 years ago

3 0

Answer and explanation:

$(6y^2-9y+4)-(-7y^2+5y+1)$ multiply the - into $-7y^2+5y+1$

$6y^2-9y+4+7y^2-5y-1$ Now add, or subtract, everything together.

$(13y^2-14y+3)$ Answer

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A six-sided number cube is tossed and a coin is flipped.

Ann [662]

Answer: The answer is 1/3, on the third attempt on the quiz, that's what it said.

4 0

3 years ago

Read 2 more answers

Of the 32 students in a class, 18 play the violin, 16 play the piano, and 7 play neither.

german

Answer:

(a)9

(b)I. 0.28125

II. 0.46875

III. 0.25

Step-by-step explanation:

There are a total of 32 students, therefore the number of elements in the Universal set, n(U)=32

$1$8 play the violin, n(V)=18\\16 play the piano, n(P)=16\\ 7 play neither, n(P \cup V)' =7$

(a)The Venn diagram is attached below.

$n(U)=n(V)+n(P)-n(V \cap P)+ n(P \cup V)'\\32=18+16+7-n(V \cap P)\\32=41-n(V \cap P)\\n(V \cap P)=41-32\\n(V \cap P)=9\\$

Therefore, 9 students play both the violin and piano.

(b)

I. Probability that the student plays the violin but not the piano

Number of Students who play violin only =18-x=18-9=9

$P(V \cap P') = \dfrac{n(V \cap P')}{n(U)}\\= \dfrac{9}{32}\\=0.28125$

ii.Probability that the student does not play the violin

Number of Students who does not play violin only =17-x+7=17-9+7=15

P(does not play violin only)

$= \dfrac{15}{32}\\=0.46875$

iii.Probability that the student plays the piano but not the violin

Number of Students who play piano only =17-x=17-9=8

$P(V' \cap P) = \dfrac{n(V' \cap P)}{n(U)}\\= \dfrac{8}{32}\\\\=0.25$

3 0

3 years ago

Somebody once told me the world is gonna roll me

nikdorinn [45]

Answer:

same

Step-by-step explanation:

8 0

3 years ago

Read 2 more answers

(b) For those values of k, verify that every member of the family of functions y = A sin(kt) + B cos(kt) is also a solution. y =

frutty [35]

Answer:

Check attachment for complete question

Step-by-step explanation:

Given that,

y=Coskt

We are looking for value of k, that satisfies 4y''=-25y

Let find y' and y''

y=Coskt

y'=-kSinkt

y''=-k²Coskt

Then, applying this 4y'"=-25y

4(-k²Coskt)=-25Coskt

-4k²Coskt=-25Coskt

Divide through by Coskt and we assume Coskt is not equal to zero

-4k²=-25

k²=-25/-4

k²=25/4

Then, k=√(25/4)

k= ± 5/2

b. Let assume we want to use this

y=ASinkt+BCoskt

Since k= ± 5/2

y=A•Sin(±5/2t)+ B •Cos(±5/2t)

y'=±5/2ACos(±5/2t)-±5/2BSin(±5/2t)

y''=-25/4ASin(±5/2t)-25/4BCos(±5/2t

Then, inserting this to our equation given to check if it a solution to y=ASinkt+BCoskt

4y''=-25y

For 4y''

4(-25/4ASin(±5/2t)-25/4BCos(±5/2t))

-25A•Sin(±5/2t)-25B•Cos(±5/2t).

Then,

-25y

-25(A•Sin(±5/2t)+ B •Cos(±5/2t))

-25A•Sin(±5/2t) - 25B •Cos(±5/2t)

Then, we notice that, 4y'' is equal to -25y, then we can say that y=Coskt is a solution to y=ASinkt+BCoskt

4 0

3 years ago

A fountain, 3 ft in diameter, sits in the center os a circular duck pond. The pond measures 3 ft from the fountain to its edge.

umka2103 [35]

Answer:

$56.55\ ft^2$

Step-by-step explanation:

We know that the diameter of the fountain is 3 feet and that it is in the center of the pond.

We know that the area of a circumference is:

$\pi(r)^2$

where r is the radius of the circumference.

further

d = 2r

Where d is the diameter of the circumference.

Then the radius $r_1$ of the source is 1.5 ft.

The radius $r_2$ of the pond is 1.5 + 3 = 4.5 ft

Finally the area of the pond is equal to the area of the ring that is shown in the image

$A = \pi(r_2)^2 - \pi (r_1)^2\\\\A = \pi(4.5)^2 - \pi(1.5)^2\\\\A = \pi(4.5^2 - 1.5^2)\\\\A = 18\pi = 56.55\ ft^2$

5 0

3 years ago