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3 years ago

Prove the following identity. sin 3θ = 3 sin θ − 4 sin3 θ

1 answer:

5 0

I'll work in x because I'm on my phone.

Proof: LHS = sin3x = sin(2x + x)
= sin2x cosx + cos2x sinx
= 2sinxcos^2x + cos^2x sinx - sin^3x
= 2sinx (1 - sin^2x) + sinx (1 - sin^2x) - sin^3x
= 2sinx - 2sin^3x + sinx - sin^3x - sin^3x
= 3sinx - 4sin^3x = RHS

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X + 8 =-12 ale Soy unni w

zimovet [89]

Answer:

x=-20

Step-by-step explanation:

x+8−8=−12−8

x=−20

3 0

3 years ago

Read 2 more answers

Carlos and Michael are collecting baseball cards. Carlos has 85 and buys 10 more each week. Michael has 120 and receives 5 more

GarryVolchara [31]

Answer:

Michael and Carlos will have the same amount after 7 weeks

Step-by-step explanation:

Assume the total number of baseball cards that Carlos and Michael need to have to be equal is y, and the amount of time in terms of weeks that it will take for this to be achieved is x.

The following expressions can be derived

For Carlos to achieve y, he will need 85 and an addition of 10 per week (x):

y=85+(10x)..........equation 1

For Michael to achieve y, he will need 120 and an addition of 5 per week (x):

y=120+(5x)..........equation 2

Equating equation 1 and 2 to solve for x

85+10x=120+5x

10x-5x=120-85

5x/5=35/5

x=7

Number of weeks it will take Michael and Carlos to have the same amount=x=7 weeks

5 0

3 years ago

If y represents a student's age, which inequality shows that you must be older than 14 to try out for the basketball team?

Lorico [155]

Answer:

week, but he must work less than ... 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 ... The graph shows the numbers of two types of custom wood tables that can ... Which system of linear inequalities. Custom Tables represents the graph? x + y = 15 ... u=50-2x. 4 = 20. Amount. Ones like not be on test lo+ll. 50-2x320 weeks. 11.

Step-by-step explanation:

7 0

3 years ago

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Rationalize the denominator and simplify. 6 /5-3

sattari [20]

Answer:

-9/5

Step-by-step explanation:

Step 1: Take the LCM in the denominator

6/5-3

multiply the numerator and denominator by 5 to make the denominator 5.

6-3 (x5)

5 1 (x5)

=6-15

= -9

6 0

3 years ago

How do you solve this please help

Andrews [41]

I’m pretty sure it’s 18
That square don’t in the corner is 90.
To find x you have to divide 2x
2x/2 = 90/2
X = 18

4 0

3 years ago