Differentiation and integration of functions

syms x

y=(11*x+1)/sqrt(x^2+22)

diff(y)

syms x

diff((11*x+1)/sqrt(x^2+22),2)

x=dsolve('Dx=(11*x+1)/sqrt(x^2+22)','x(0)=0'))

grid

I have this code, but in line 6 its mistake. Can you help me?

I must to find

Answer 1

[Bjorn Gustavsson]

You need to change from assignment to equality:

x=dsolve('Dx==(11*x+1)/sqrt(x^2+22)','x(0)=0')

But this is most likely not the way to solve this task.

HTH

[Artur Shpak]

I know it, but how??

Answer 2

[David Hill]

syms x;
y=(11*x+1)/sqrt(x^2+22);
dy=diff(y);
ddy=diff(dy);
for x=1:3
    Dy(x)=double(subs(dy));
    DDy(x)=double(subs(ddy));
end
Y=@(x)(11*x+1)./sqrt(x.^2+22);
I=integral(Y,1,3);