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3 years ago

Find all solutions to the equation sin(3x)cosx-sinx cos(3x)=0 on the interval [0,2pi]

1 answer:

4 0

Please have in mind that sin(A - B) = sin(A)cos(B) - cos(A)sin(B) 
So what we do is:
sin(3x)cos(x) - sin(x)cos(3x) = 0 => sin(3x - x) = 0 

sin(2x) = 0 

2x = 0, π, 2π, 3π, 4π 

x = 0, π/2, π, 3π/2, 2π
With this, even though not giving you all the answers, will help you greatly to get them. I know you will get the answers with no problems.

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Dwayne starts at the surface of the water and swims to -25 feet. From there he swims +10 feet to see the fish and then back down

d1i1m1o1n [39]

(-25) + 10 + (-5) = -20 feet is his current position. To reach zero, he should add 20 feet to his altitude.

7 0

3 years ago

Expanded form of 680,705

denis23 [38]

$\huge\boxed{600,000 + 80,000 + 700 + 5}$

To find expanded form, we need to split up the digits. When you do that, you take one digit and cut off everything to the left of it, then make everything to the right zeros.

$600,000 + 80,000 + 0 + 700 + 0 + 5$

We don't need to keep the zeros.

$\boxed{600,000 + 80,000 + 700 + 5}$

We can check this by adding the numbers back up to get $680,705$ .

$680,000 + 700 + 5$

$680,700 + 5$

$680,705$

6 0

3 years ago

Can someone pls help me solve this question!!!!!!!

KiRa [710]

Total of 90 fish:

c + p = 90

Charlie gave 1/4 c to Peter. Now

Charlie has c - (1/4) c

Peter has p + (1/4) c

Peter gave 2/5 of his to Charlie. Now

Peter has p + (1/4) c - 2/5( p + (1/4) c )

Charlie has c - (1/4) c + 2/5( p + (1/4) c )

And then they had equal number:

c - (1/4) c + 2/5( p + (1/4) c ) = p + (1/4) c - 2/5( p + (1/4) c )

Let's do the easy subtractions then multiply by 20 to clear the fractions,

(3/4) c + 2/5( p + (1/4) c ) = 3/5( p + (1/4) c )

15c + 8p + 2c = 12p + 3c

14c = 4p

7c = 2p

c + p = 90

2c + 2p = 180

2c + 7c = 180

9c = 180

c = 20

p = 70

Answer: Charlie started with 20, Peter with 70

Check:

Initially C:20, P:70

1/4(20)=5 to P

C:15, P:75

(2/5) 75 = 30 to C

C:45, P45

Good

3 0

3 years ago

I don’t know what to do

Gre4nikov [31]

Answer:

is it on a website or paper?

Step-by-step explanation:

6 0

3 years ago

Andrew can type 1.5 pages in 10 minutes. At this rate, how many pages can Andrew type in 1 hour? pls help me hurry have do be do

rodikova [14]

Answer:

Andrew will be able to type 9 pages in 1 hour

Step-by-step explanation:

1.5 x 6 = 9

Hope this helped !

3 0

3 years ago

Read 2 more answers