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Question

Question: $\int 1^x.2^x.3^x.....n^x dx$...

1x.2x.3x.....nxdx\int 1^x.2^x.3^x.....n^x dx

Answer

(n!)xln(n!)+C\frac{(n!)^x}{\ln(n!)} + C

Explanation

Solution

The integrand 1x.2x.3x.....nx1^x.2^x.3^x.....n^x simplifies to (123n)x=(n!)x(1 \cdot 2 \cdot 3 \cdot \dots \cdot n)^x = (n!)^x. The integral then becomes (n!)xdx\int (n!)^x dx. This is a standard integral of the form axdx\int a^x dx, where a=n!a = n!. Using the formula axdx=axlna+C\int a^x dx = \frac{a^x}{\ln a} + C, we substitute a=n!a = n! to get the result (n!)xln(n!)+C\frac{(n!)^x}{\ln(n!)} + C.