MATLAB: 3-D-plot doesn’t look like on Wolfram Alpha

analysisMATLABplot

I'm confused. By typing:

[x,y] = meshgrid(-2:0.2:2)
z = sin(x)./(y.^2+1)
surf(x,y,z)

I receive a totally different plot.

It looks the same to me as long as you enter

plot sin(x)/(y^2+1) from x=-2 to 2 and y=-2 to 2

into Wolfram Alpha

Alternately,

syms x
solve(1.08393 == (1+x)/(1-x), x)

Hi Niklas,

You need to set 'ReturnConditions' to true to return any parameters in the solution and conditions on the solution. Therefore,

S = solve(x^2-(8*x)+15<=1, 'ReturnConditions',true);
S.conditions,
ans =
 x <= 2^(1/2) + 4 & 4 - 2^(1/2) <= x
                       in(y, 'real')

which is the solution interval: 2.5858 <= x <= 5.4142