function x=Newtond(m,x0,e,c)
if find(m>0 & m<10)
c=1-(1-subs(f_1,m))^2;
elseif find(m>=10)
c=1-(1-subs(f_2,m))^2;
elseif find(m==0)
c=1;
else
c=0;
end
if find(c>subs(f_2,10))
fx=f_1-c;
x_a=x0;
elseif find(c<=subs(f_2,10))
fx=f_2-c;
x_a=10;
end
x_b=x_a-subs(fx,x_a)/subs(diff(fx),x_a);
k=1;
while abs(x_a-x_b)>e;
k=k+1;
x_a=x_b;
x_b=x_a-subs(fx,x_a)/subs(diff(fx),x_a);
if find(k>100)
% x=1;
break;
end
end
%disp(k);
x=x_b;
%disp(x)