tangent line

dannatyler

New member
Joined
May 8, 2010
Messages
7
Another question:
Find the equation of the tangent line to the graph of y=arcsin (x/2) at the point where x=1.

This is what I got so far but I'm not sure if I'm right:
F(1) = arcsin (1/2) F(1) = pi/6
y'= 1/2 sqrt(1-x^2/4)
m= 1/2 sqrt (1-1/4) = sqrt 3/3

equation would be y=sqrt3/3(x-1)+pi/6????? Doesn't seem correct...
 
given: f(x) = arcsin(x/2),find equation of tangent line to f(x) when x = 1.\displaystyle given: \ f(x) \ = \ arcsin(x/2), find \ equation \ of \ tangent \ line \ to \ f(x ) \ when \ x \ = \ 1.

f(1) = π/6\displaystyle f(1) \ = \ \pi/6

f(x) = 14x2 = m\displaystyle f'(x) \ = \ \frac{1}{\sqrt{4-x^2}} \ = \ m

f(1) = 3/3 = m\displaystyle f'(1) \ = \ \sqrt3/3 \ = \ m

yπ/6 = (3/3)(x1)\displaystyle y-\pi/6 \ = \ (\sqrt3/3)(x-1)

y = (3/3)(x1)+π/6, see graph.\displaystyle y \ = \ (\sqrt3/3)(x-1)+\pi/6, \ see \ graph.

[attachment=0:m2bza2ni]xyz.jpg[/attachment:m2bza2ni]
 

Attachments

  • xyz.jpg
    xyz.jpg
    16 KB · Views: 212
dannatyler said:
just one question for. Isn't Y'= 1/2sqrt(1-x^2/4)? It is.

Instead of staring at the solution - get a paper and pencil and work through it.

121(x2)2  =  124x24  =  14x2\displaystyle \frac{1}{2\sqrt{1-(\frac{x}{2})^2}} \ \ = \ \ \frac{1}{2\sqrt{\frac{4-x^2}{4}}} \ \ = \ \ \frac{1}{\sqrt{4-x^2}}[/spoiler:28y2mocx]
 
Dx[arcsin(x/2)] = 1/21x2/4 = 1/24x2/2\displaystyle D_x[arcsin(x/2)] \ = \ \frac{1/2}{\sqrt{1-x^2/4}} \ = \ \frac{1/2}{\sqrt{4-x^2}/2}

=  (12)(24x2) = 14x2\displaystyle = \ \ \bigg(\frac{1}{2}\bigg)\bigg(\frac{2}{\sqrt{4-x^2}}\bigg) \ = \ \frac{1}{\sqrt{4-x^2}}
 
Top