Any onr can help me

[KSSV]

What have you attempted for your Home work?

[Jack William]

I want to compare my solution with the expert solution

[KSSV]

Attach your solution.

[Jack William]

Q4% 
s=0; 
for i=1:n 
    s=s+i;
end 
disp(s)

[Jack William]

Q5% y=0; for k = 0:n y = y + ((n/k) * (x^k) * ( a^a-x)); end disp (y)

[KSSV]

n = 10;
s = sum(1:n)

Answer 1

[Jan]

% Sum of i (i = 1:n):
s = n * (n+1) / 2

Unrecognized function or variable 'n'.

Gauss is faster and easier.

% Your solution:
y = 0;
for k = 0:n
    y = y + ((n/k) * (x^k) * (a^a-x));
    %                           ^ nope, this should be (n-k)
end
disp(y)

This cannot work: n/k is Inf, if k=0. Therefore the loop is Inf in every case.

Hint: The power operator ^ is very expensive. You can avoid it:

x  = 0.98;
a  = 1.2;
n  = 17;

xk  = x;
ank = a^(n - 1);
y   = 0;
for k = 1:n
    y   = y + (n / k * xk * ank);
    xk  = xk * x;
    ank = ank / a;
end
y

y = 0;
for k = 1:n
    y   = y + n / k * x^k * a^(n-k);
end
y

This is "much faster", but speed does not matter for such tiny problems. The accumulated rounding error is acceptable: In opposite to the sum, the product is numerically stable.