Plz plz plz plz help me

Simplify using trigonometric identities<br> 2sinθ - sin2θ cosθ

Anit [1.1K]

Double angle identity for sine:

$\sin(2x) = 2 \sin(x) \cos(x)$

$\implies 2 \sin(\theta) - \sin(2\theta) \cos(\theta) = 2 \sin(\theta) - 2 \sin(\theta) \cos^2(\theta)$

Factorize the left side.

$2 \sin(\theta) - 2 \sin(\theta) \cos^2(\theta) = 2 \sin(\theta) \left(1 - \cos^2(\theta)\right)$

Pythagorean identity:

$\cos^2(x) + \sin^2(x) = 1$

$\implies 2 \sin(\theta) \left(1 - \cos^2(\theta)\right) = 2 \sin^3(\theta)$

so that

$\boxed{2 \sin(\theta) - \sin(2\theta) \cos(\theta) = 2 \sin^3(\theta)}$

8 0

1 year ago

100 Points! What are the classifications of each system?

alexdok [17]

Answer:

Part 1) Is a inconsistent system

Part 2) Is a consistent independent system

Part 3) Is a consistent dependent system

see the attached figure

Step-by-step explanation:

we know that

If a system has at least one solution, it is said to be consistent .

If a consistent system has exactly one solution, it is independent .

If a consistent system has an infinite number of solutions, it is dependent

If a system not have solution, it is said to be inconsistent

Part 1) we have

$x+5y=-2\\x+5y=4$

This system of linear equations has two parallel lines (their slopes are equal) with different y-intercept

so

The lines don't intersect

The system has no solution

therefore

Is a inconsistent system

Part 2) we have

$y=3x+4\\-2x+y=4$

we know that

If two lines have different slopes, then the lines intersect at one point and the system of equations has one solution

In this problem, the lines have different slopes (m=3 and m=2)

so

The lines intersect at one point

The system has one solution

therefore

Is a consistent independent system

Part 3) we have

$3x+y=4$ ----> equation A

$-6x-2y=-8$ ----> equation B

Multiply equation A by -2 both sides

$-2(3x+y)=-2(4)$

$-6x-2y=-8$ ----> equation C

Compare equation B and equation C

Are identical lines

so

The system has infinity solutions

therefore

Is a consistent dependent system

4 0

3 years ago

A recipe calls for blueberry muffins cost for 2 3/4 cup of blueberries. You are making 1/3 of the recipe. How much blueberries s

tester [92]

Answer: 8/9 cups

Step-by-step explanation:

The word 'of' means 'times' as far as fractions are concerned. In this case, we have 1/3 of 2 1/3.

First, it is a good idea to make 2 1/3 an improper fraction - as 8/3, so now we have:

1/3 of 8/3, but since 'of' means 'times' we have,

1/3 x 8/3 = 8/9

The answer is 8/9 cups.

7 0

3 years ago

PLZ HELP ASAP ILL GIVE BRAINLEST

lianna [129]

Answer:

2.25

Step-by-step explanation:

-9/-4= 2.25

3 0

2 years ago

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Anyone know how to do this?

alexgriva [62]

Answer:

60.22in^2.

Step-by-step explanation:

First, find the area of the rectangle. 14.1x7=98.7.

Then, we need to find the area of the circle and subtract it from the area of the rectangle.

The area of the circle is pi*r^2. so, pi*3.5^2 is about 38.48. (The radius is half of the diameter, so the radius would be 3.5).

Since there are two halves of the circle, we can just subtract 38.48 from 98.7 so get the area of the shaded region. So, the area of the yellow area is 60.22in^2.

4 0

2 years ago

Read 2 more answers