Reputation
2,348
Top tag
Next privilege 2,500 Rep.
Create tag synonyms
Badges
3 15 33
Newest
 Yearling
Impact
~159k people reached

Nov
8
comment Find the equations to the normal lines of a curve where $x = 4$.
Oh! Right! The normal line. I got it now. Thank you!
Nov
8
comment Find the equations to the normal lines of a curve where $x = 4$.
I see. $\frac{5}{10}$ would be the slope for a tangent line that passes by $(4,3)$. The tangent line equation would be $$y-3=\frac{5}{10}(x-4)$$ Which is $$y=\frac{x}{2}+1$$ It concerns me, because apparently the answer should be $$y=-2x+11$$ According to my book.
Nov
8
comment Find the equations to the normal lines of a curve where $x = 4$.
I have calculated the implicit derivative to be $$\frac{2x-y}{2y+x}$$ So the slopes of the tangent lines at $x = 4$ should be obtained by evaluating $x=4$ in this derivative, rather than the original function $y^2+4y-16=5$, no? If I plug $x=4$ in this derivative, I would get that $y=0$.
Nov
8
comment Find the equations to the normal lines of a curve where $x = 4$.
@G-man I mean getting the derivative of $y^2+4y-16=5$. I assumed that you could calculate derivatives of functions only.
Nov
8
comment Find the equations to the normal lines of a curve where $x = 4$.
@G-man ah, well, I didn't know that. So this curve is not a function? Does that mean I can't derive it? (I was guessing deriving it would be part of the solution or something like that)
Nov
8
asked Find the equations to the normal lines of a curve where $x = 4$.
Nov
8
accepted Finding the equation of the tangent line for the curve $f(x)=x^2+\frac{2}{x}$ parallel to $3y-2x=5$
Nov
8
asked Finding the equation of the tangent line for the curve $f(x)=x^2+\frac{2}{x}$ parallel to $3y-2x=5$
Nov
6
accepted Calculating the derivative of $\csc^2(4x)$
Nov
6
asked Calculating the derivative of $\csc^2(4x)$
Nov
6
revised Calculating a simpler derivative for $\frac{1+\cot x}{2- \sec x}$
added 3 characters in body
Nov
6
asked Calculating a simpler derivative for $\frac{1+\cot x}{2- \sec x}$
Nov
3
comment Calculate the derivative of the product of three functions $e^x\cdot \ln(x) \cdot \cot x$
@Kaster that looks pretty cool - how did you reach that conclusion?
Nov
3
asked Calculate the derivative of the product of three functions $e^x\cdot \ln(x) \cdot \cot x$
Nov
3
accepted The derivative of $-e^{\sqrt{2}\cdot x}\cdot 5x^3$
Nov
3
asked The derivative of $-e^{\sqrt{2}\cdot x}\cdot 5x^3$
Oct
29
awarded  Notable Question
Oct
13
accepted Differentiating $\sqrt{x}+\sqrt{x^3}+\sqrt[3]{x^2}$
Oct
13
asked Differentiating $\sqrt{x}+\sqrt{x^3}+\sqrt[3]{x^2}$
Oct
1
accepted Doing $\lim_{x\to0}\frac{\sin x - \tan x}{x^2\cdot\sin 2x}$ without L'Hopital