How do I rearrange this equation involving trig functions to solve for x?

  • Thread starter Aristodol
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In summary, to solve for x in the equation sin^2 x(tan x) = 1356, follow these steps: 1. Use the identity tan(x) = sin(x)/cos(x). 2. Substitute for cos(x) using cos(x) = sqrt(1 - sin^2(x)). 3. Take the square on both sides and rearrange the terms to get a 6th order polynomial. 4. Substitute y = sin^2(x) and solve the resulting 3rd order polynomial for y. 5. Once you have y, solve for x (ensuring that x is not a single value function of y).
  • #1
Aristodol
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i am unsure about how to rearrange this equation so that I can solve for x an unknown angle. Please help.

we have:

sin^2 x(tan x)=1356

it is very simple I no but I just can't remember the way to go about solving this problem, especially because of the sin^2
 
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  • #2
Follow the steps below:

1. [tex] tan(x) = \frac{sin(x)}{cos(x)} [/tex]
2. [tex] cos(x) = \sqrt{1 - sin^2(x)} [/tex]
3. take square on both size, and re-arrange the terms, you will get a 6th order polynomial
4. do a substitution [tex] y = sin^2(x) [/tex], then you will have a 3th order polynomial
5. solve the 3rd order polynomial for y...
6. as soon as you have y, you will get x... (make sure x is not a single value function of y)
 
  • #3
x term

To rearrange this equation, you can start by isolating the trig function with the unknown angle, which in this case is tan x. You can do this by dividing both sides of the equation by sin^2 x, which will give you:

tan x = 1356 / sin^2 x

Next, you can use the inverse trig function, arctan, to isolate the unknown angle x. This will give you:

x = arctan(1356 / sin^2 x)

However, since you are unsure about how to handle the sin^2 x term, it is important to note that you can also use the trig identity sin^2 x + cos^2 x = 1 to rewrite the equation as:

(sin x / cos x)^2 (tan x) = 1356

Then, you can substitute in the identity for sin^2 x and solve for tan x:

(tan x / cos^2 x) (tan x) = 1356

tan^2 x = 1356 / cos^2 x

Finally, you can take the square root of both sides to solve for tan x:

tan x = ±√(1356 / cos^2 x)

Remember that there are two possible solutions for x, so you will need to plug in both positive and negative values for the square root to find both solutions.

I hope this helps and remember to always check your solutions by plugging them back into the original equation to make sure they are correct.
 

FAQ: How do I rearrange this equation involving trig functions to solve for x?

What is trigonometry?

Trigonometry is a branch of mathematics that deals with the study of triangles and the relationships between their sides and angles.

What is an equation involving trigonometric functions?

An equation involving trigonometric functions is an equation that contains one or more trigonometric functions, such as sine, cosine, or tangent, and is used to solve for unknown values.

How is trigonometry used in equations?

Trigonometry is used in equations to solve for unknown values in triangles, as well as in many real-life applications such as engineering, physics, and astronomy.

What are some common trigonometric identities used in equations?

Some common trigonometric identities used in equations include the Pythagorean identities, which relate the sides of a right triangle, and the double angle identities, which express trigonometric functions in terms of their double angles.

How can I solve a trigonometric equation?

To solve a trigonometric equation, you can use algebraic manipulation, trigonometric identities, and properties of trigonometric functions to isolate the variable and find its value. You can also use a calculator or trigonometric tables to find approximate solutions.

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