I've tried for the last hour and a half, but I can't figure out how to solve this problem. I'd really appreciate some help.
$$\frac{50\cdot 2^x}{1+2^{-x}} = 4$$
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$\begingroup$ The first thing I would do is let y= 2^x so the equation become 50y/(1+ y)= 4. Now multiply both sides by 1+ y. Can you solve 50y= 4(1+ y). Can you solve that for y? Once you have 2^x= y, taking logarithms of both sides xlog(2)= log(y). $\endgroup$– user247327Commented Apr 28, 2017 at 16:39
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$\begingroup$ @user247327 The resulting equation would be $50y/(1+1/y)=4$ $\endgroup$– ΧpẘCommented Apr 28, 2017 at 18:08
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1 Answer
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Guide:
$$\frac{50(2^x)}{1+2^{-x}} = 4$$
Let $y = 2^x$
$$50y= 4(1+y^{-1})$$
Multiply $y$ throughout and you should get a quadratic eqution.
After you solve for $y$ then solve for $x$.
answered Apr 28, 2017 at 16:38