Finding the Equation of a Tangent

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SUMMARY

The discussion focuses on finding the equation of the tangent line to the function y=3csc(x) at the point x=π/4. The user successfully differentiates the function to obtain the slope, represented as y=3(-cot(x)csc(x)). By substituting x=π/4 into the derivative, they calculate the slope as 3(-cot(π/4)csc(π/4)). The user seeks clarification on simplifying the expressions involving csc and cotangent, ultimately determining that 3csc(π/4) simplifies to 3√2/2.

PREREQUISITES
  • Understanding of trigonometric functions, specifically cosecant and cotangent.
  • Knowledge of differentiation techniques in calculus.
  • Familiarity with the tangent line equation, y=mx+b.
  • Ability to evaluate trigonometric functions at specific angles, such as π/4.
NEXT STEPS
  • Study the properties and graphs of trigonometric functions, focusing on cosecant and cotangent.
  • Practice differentiation of trigonometric functions using the product and chain rules.
  • Learn how to derive and apply the tangent line equation in various contexts.
  • Explore the unit circle to better understand the values of trigonometric functions at key angles.
USEFUL FOR

Students studying calculus, particularly those focusing on trigonometric functions and their applications in finding tangent lines. This discussion is also beneficial for educators seeking to clarify concepts related to differentiation and trigonometric identities.

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Homework Statement


Find the equation of the tangent at the point indicated
y=3cscx
x=pi/4

2. The attempt at a solution

So to do the question you need a point (which I am given), the slope and then you need to substitute that all into y=mx+b.

I believe I have differentiated correctly with

y=3(-cot(x)csc(x))

Then I find the slope by inserting pi/4 into the differentiated equation

y=3(-cot(pi/4)csc(pi/4))

After this is done I put everything into y=mx+b, and this is where my problem is. Is there anyways to simplify 3csc(pi/4) and 3(-cot(pi/4)csc(pi/4))? I think I remember doing something similar in math a long time ago but I forgot now. The final answer does not include -cot or csc so there must be a way I don't remember.
 
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What is cosec and cotangent in terms of the other trig functions?

1/(sin x) = csc x
1/( tan x) = cot x

So 3 csc (pi/4) = [itex]\frac{3}{\sin (\pi/4)}[/itex].

The exact value for sin (pi/4) is 1/(sqrt2) so..
[itex]3 \csc (\pi/4) = \frac{3}{\sqrt{2}} = \frac{3\sqrt{2}}{2}[/itex]

So the same for cot, knowing tan (pi/4) = 1.
 

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