【单选题】二元 溶液 , T, P 一定时 ,Gibbs—Duhem 方程的正确形式是 (). A. X 1 dlnγ 1 /dX 1 + X 2 dlnγ 2 /dX 2 = 0 B. X 1 dlnγ 1 /dX 1 + X 2 dlnγ 2 /dX 1 = 0 C. X 1 dlnγ 1 /dX 2 + X 2 dlnγ 2 /dX 1 = 0 D. X 1 dlnγ 1 /dX 1 – X 2 dlnγ 2 /dX 1 = 0

设$f(x)$是连续的奇函数，则定积分$\int_{-1}^1 f(x)dx=$ A: $2\int_{-1}^0 f(x)dx$ B: $\int_{-1}^0 f(x)dx$ C: $\int_{0}^1 f(x)dx$ D: $0$

\( d(\arcsin x) \)=（ ）. A: \( {1 \over {\sqrt {1 - {x^2}} }}dx \) B: \( - {1 \over {\sqrt {1 - {x^2}} }}dx \) C: 0 D: 1

【单选题】Which of the following matrices does not have the same determinant of matrix B: [1, 3, 0, 2; -2, -5, 7, 4; 3, 5, 2, 1; -1, 0, -9,-5] A. [1, 3, 0, 2; -2, -5, 7, 4; 0, 0, 0, 0; -1, 0, -9, -5] B. [1, 3, 0, 2; -2, -5, 7, 4; 1, 0, 9, 5; -1, 0, -9, -5] C. [1, 3, 0, 2; -2, -5, 7, 4; 3, 5, 2, 1; -3, -5, -2, -1] D. [1, 3, 0, 2; -2, -5, 7, 4; 0, 0, 0, 1; -1, 0, -9, -5]

设f(x)=(1/(1+x^2))+x^3∫(0到1)f(x)dx,求∫(0到1)f(x)dx

∫1上限0下限根号（4－x^2）dx=?

四个选项中是广义积分的为（ ）。 A: \( \int_0^1 { { 1 \over x}dx} \) B: \( \int_{ - 1}^0 { { 1 \over {x - 1}}dx} \) C: \( \int_{1}^2 { { \ lnx}dx} \) D: \( \int_{ - 1}^0 { { 1 \over {\sqrt {1 - x} }}dx} \)

不计算积分比较∫【0到1】(x^2)dx与∫【0到1】（x^5）dx积分值的大小

由\( y = {x^2} - 1,\;y = 0 \)围成的平面图形面积可表示为( )。 A: \( \int_{ - 1}^1 {\left( { - {x^2} + 1} \right)} dx \) B: \( \int_{ - 1}^1 {\left( { { x^2} - 1} \right)} dx \) C: \( \int_0^1 {\left( { - {x^2} + 1} \right)} dx \) D: \( \int_0^1 {\left( { { x^2} - 1} \right)} dx \)

积分计算∫(上限π下限0)(1-sinx)^(1/2)dx