Question

MATLAB几道题

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Answer 1

第一题
m=-1;
x(1)=3;
x(2)=(x(1)+m/x(1))/2;
i=2;

while abs(x(i)-x(i-1))>1e-6&i<10000
i=i+1;
x(i)=(x(i-1)+m/x(i-1))/2;

end
if abs(x(i)-x(i-1))<1e-6
plot(x)
disp(['收敛，',num2str(x(i))])
elseif abs(x(i)-x(i-1))>1e-6
plot(x)
disp(['不收敛，'])
end

m=-1计算结果 不收敛 而m=1时计算结果收敛

第二题
p=7;
i=2;
a(1)=1;
a(2)=1/(2^p);
x(1)=1;
x(2)=1+1/(2^p);
while abs(x(i)-x(i-1))>1e-17&i<100000
i=i+1;a(i)=1/(i^p);
x(i)=sum(a);
end
if abs(x(i)-x(i-1))<1e-17
plot(x)
disp(['收敛，'])
s=vpa(x(i),17)
elseif abs(x(i)-x(i-1))>1e-17
plot(x)
disp(['不收敛，'])
end
收敛，

s =

1.0083492773819207

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