How Do You Isolate A in the Equation n=sin[(A+B)/2]/sin(B/2)?

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A+B}{2}) In summary, the conversation is about solving for A using the formula n=sin[(A+B)/2]/sin(B/2). The attempt at a solution involved expanding the formula to sinAcosB + cosAsinB, but did not provide much help. The suggestion was to use the internet and the formula sin(\frac{B}{2}) = \sin(\frac{B}{2}) = \frac{1-cos(B)}{2} \sin(\frac{A+B}{2}).
  • #1
joemama69
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Homework Statement



given this formula, i have to solve for A

n=sin[(A+B)/2]/sin(B/2)


Homework Equations





The Attempt at a Solution



Heres how far I got

2nsin(B/2) = sin(A+B) i know this can expand out to
=sinAcosB + cosAsinB but this isn't much help. Anyone got a suggestion
 
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  • #2
joemama69 said:

Homework Statement



given this formula, i have to solve for A

n=sin[(A+B)/2]/sin(B/2)


Homework Equations





The Attempt at a Solution



Heres how far I got

2nsin(B/2) = sin(A+B) i know this can expand out to
=sinAcosB + cosAsinB but this isn't much help. Anyone got a suggestion

Made me think of the interweb

[tex]sin(\frac{B}{2}) = sin(\frac{B}{2}) = \frac{1-cos(B)}{2}[/tex]
 
Last edited:

FAQ: How Do You Isolate A in the Equation n=sin[(A+B)/2]/sin(B/2)?

What is the formula for solving for A in Sin(A+b)?

The formula for solving for A in Sin(A+b) is A = Sin^-1(sin(b) * cos(A) + cos(b) * sin(A)).

Can you explain the concept of "solving for A in Sin(A+b)"?

Solving for A in Sin(A+b) means finding the value of A in a trigonometric equation where the sine function is applied to the sum of A and another angle, b.

What are the steps for solving for A in Sin(A+b)?

The steps for solving for A in Sin(A+b) are as follows:
1. Use the sine function to set up the equation.
2. Expand the equation using the sum formula for sine.
3. Simplify the equation using trigonometric identities.
4. Isolate the term with A on one side of the equation.
5. Take the inverse sine of both sides to solve for A.

Can you provide an example of solving for A in Sin(A+b)?

For example, if we have the equation Sin(A+45°) = 0.5, we can solve for A as follows:
1. Sin(A+45°) = 0.5
2. Sin(A) * Cos(45°) + Cos(A) * Sin(45°) = 0.5
3. Sin(A) * (sqrt(2)/2) + Cos(A) * (sqrt(2)/2) = 0.5
4. (sqrt(2)/2) * (Sin(A) + Cos(A)) = 0.5
5. Sin(A) + Cos(A) = 0.5 * (2/sqrt(2))
6. Sin(A) + Cos(A) = sqrt(2)/2
7. A = Sin^-1(sqrt(2)/2) - Cos^-1(sqrt(2)/2)
8. A ≈ 35.26° or A ≈ 180° - 35.26° = 144.74°
So, the solutions for A are A = 35.26° or A = 144.74°.

What is the importance of solving for A in Sin(A+b)?

Solving for A in Sin(A+b) is important in trigonometry as it allows us to find the value of an unknown angle in a trigonometric equation. It is also useful in solving real-world problems that involve angles and sine functions.

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