TÌM ∫ ( X4+ + + + X3 X2 X 1 ) DX =

Câu 1. Tìm _∫ ( ^x

^{+ + + + x}

^x

^{x 1} ) ^{dx = ?}

x x x x

A.

+ + + + + x C . B.

+ + + + x . C.

5 4 3 2

x + + + + + x x x x C .D. 4 x

+ 3 x

+ 2 x + 1 .