Re: DSolving(?) for a given tangent
- To: mathgroup at smc.vnet.net
- Subject: [mg81379] Re: DSolving(?) for a given tangent
- From: Szabolcs Horvát <szhorvat at gmail.com>
- Date: Fri, 21 Sep 2007 03:07:43 -0400 (EDT)
- References: <fct9c4$r6e$1@smc.vnet.net>
Szabolcs Horvát wrote:
> AngleWyrm wrote:
>> f[x_] := E^(0.22 x);
>> Plot[f[x], {x, 6, 36}]
>>
>> Which plots a nice escalating curve.
>>
>> What I would like to know is: Where is the point {x,f[x]} that has a
>> 45-degree tangent line;
>
> f[x_] := Exp[a x]
>
> Solve[f'[x] == 1/2, x]
This should be Solve[f'[x] == 1, x], of course!!!!