How to make M into a symsfun?

% This program computes for the Tangent Line / Normal Line of a curve % about a given point
                   %define x for symbolic processing
syms x 
%IDENTIFY the function f(x)
f(x) = 4*x^2 - 2*x + 1

%DETERMINE the point of tangency (This will be a random point)
x0=randi([-5,5])
%SOLVE for the Ordinate of the point of tangency
y0=f(x0);  %Evaluate y given value fo x

%FIND the slope function
yprime=  diff(f)      %Solve for the first derivative

%Determine the slope at the given x0
m = limit(yprime,x,x0)     %Evaluate the slope

%Solve the equation of the tangent line
ytangent= m*(x-x0) + y0

%Solve the Equation of the normal line
ynormal= -1/ytangent


%I have to somehow input the value of x0 into yprime without making m into
%a syms because it affects the other equations. m = f'(c) where c=x0

[KSSV]

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Answer 1

[Walter Roberson]

% This program computes for the Tangent Line / Normal Line of a curve % about a given point
                   %define x for symbolic processing
syms x 
%IDENTIFY the function f(x)
f(x) = 4*x^2 - 2*x + 1

f(x) = 

%DETERMINE the point of tangency (This will be a random point)
syms x0
%SOLVE for the Ordinate of the point of tangency
y0=f(x0);  %Evaluate y given value fo x

%FIND the slope function
yprime=  diff(f)      %Solve for the first derivative

yprime(x) = 

%Determine the slope at the given x0
m(x0) = limit(yprime,x,x0)     %Evaluate the slope

m(x0) = 

%Solve the equation of the tangent line
ytangent= m*(x-x0) + y0

ytangent(x0) = 

%Solve the Equation of the normal line
ynormal= -1/ytangent

ynormal(x0) =