Question about finding a tangent

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Homework Statement



Show that, for each real number t \in the interval (0, 1], the curve given by:

y=ln(\frac{x+\sqrt{1+x^{2}}}{1+\sqrt{2}})

has a tangent line with slope t. Find the points on the curve at which the tangent line has slope 2/3.

The Attempt at a Solution



I found the first derivative of this curve to be:

dy/dx=1/\sqrt{(1+x^{2})}

but now not sure how to proceed.

What do they mean when they ask me to show that for each t has a tangent line with slope t?

any help appreciated!

Also to find the points with dy/dx=3 I did this:

dy/dx=1/\sqrt{(1+x^{2})} =2/3 >>>> x=\pm \sqrt{5}/2
 
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kwal0203 said:

Homework Statement



Show that, for each real number t \in the interval (0, 1], the curve given by:

y=ln(\frac{x+\sqrt{1+x^{2}}}{1+\sqrt{2}})

has a tangent line with slope t. Find the points on the curve at which the tangent line has slope 2/3.

The Attempt at a Solution



I found the first derivative of this curve to be:

dy/dx=1/\sqrt{(1+x^{2})}

but now not sure how to proceed.

What do they mean when they ask me to show that for each t has a tangent line with slope t?

any help appreciated!

Also to find the points with dy/dx=2/3 I did this:

dy/dx=1/\sqrt{(1+x^{2})} =2/3 >>>> x=\pm \sqrt{5}/2

Do what you just did for ##t## instead of 2/3. For the points on the curve you probably want the y values too.
 
LCKurtz said:
Do what you just did for ##t## instead of 2/3. For the points on the curve you probably want the y values too.

Oh of course, lol! thanks
 
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