Solve Multivariable Sketch Problem: Power of e Function

seiferseph
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Here is the problem I'm having some trouble with. The answer is fairly simple, it is the power of the e function. (the parabola x = y^2 + 1) I'm not sure how to get that, i could use some hints/help, thanks!
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Think about what values for the power of an exponent give a result greater than one.
 
Are you aware that "The answer is fairly simple, it is the power of the e function. (the parabola x = y^2 + 1)" is NOT precisely true? That is, the region you are asked to sketch is NOT the parabola itself. The parabola is a boundary of the region. Indeed if you think about the fact that "power of the e function" is NOT x= y^2+ 1 nor a parabola, you might see what StatusX means!
 
I'll be kind: recall that e^w \geq 1 if, and only if, w\geq 0, that is, if, and only if the exponent of e is greater than or equal to 0. You are asked to find (and sketch) all points in xy-plane (e.g. all values of x and y) such that e^{1-x+y^{2}}\geq 1, which occurs if, and only if, 1-x+y^{2}\geq 0 which describes the region in the xy-plane bounded by (and to the left of) the parabola x=1+y^{2}.
 
benorin said:
I'll be kind: recall that e^w \geq 1 if, and only if, w\geq 0, that is, if, and only if the exponent of e is greater than or equal to 0. You are asked to find (and sketch) all points in xy-plane (e.g. all values of x and y) such that e^{1-x+y^{2}}\geq 1, which occurs if, and only if, 1-x+y^{2}\geq 0 which describes the region in the xy-plane bounded by (and to the left of) the parabola x=1+y^{2}.

ohh, i see, i forgot that to get that's how to get the entire function greater than 1, i get it now, thanks everyone!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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