A catenary curve can be described by the following function:(adsbygoogle = window.adsbygoogle || []).push({});

y= a/2 (e^{x/a}+ e^{-x/a})

where a is a non-zero constant

By selecting sutable axes, devise an equation that will produce the gateway arch.

Right next to the question is a graph of an arch that is 630 feet high (on the y axis) and 630 feet long (on the x axis).

I have no idea where to start. I was thinking that I could substitute the x and y values in of 630 to find the a value and thus the normal function (since its constant). But then why not just ask for that? Why go and say devise an equation, i dont follow.

Please, I would really appreciate someone getting me started on this!

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# Gateway/exponential formula

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