四級(jí)數(shù)學(xué)試卷及答案

四級(jí)數(shù)學(xué)試卷及答案一、選擇題（每題3分，共30分）1.已知函數(shù)f(x)=2x-3，求f(5)的值。A.7B.4C.2D.12.計(jì)算下列極限lim(x→0)(sin(x)/x)的值。A.0B.1C.-1D.23.已知等差數(shù)列{an}的首項(xiàng)a1=2，公差d=3，求a5的值。A.14B.17C.20D.234.計(jì)算定積分∫(0,1)x^2dx的值。A.1/3B.1/2C.2/3D.15.已知函數(shù)f(x)=x^3-3x^2+2x，求f'(x)的值。A.3x^2-6x+2B.3x^2-6x+1C.3x^2-6x+3D.3x^2-6x-26.計(jì)算下列二項(xiàng)式展開式(1+x)^5的通項(xiàng)公式。A.C(5,k)x^kB.C(5,k)x^(5-k)C.C(5,k)x^kD.C(5,k)x^(5-k)7.已知矩陣A=\[\begin{bmatrix}1&2\\3&4\end{bmatrix}\]求矩陣A的行列式值。A.-2B.2C.-5D.58.計(jì)算下列極限lim(x→∞)(x^2+3x+2)/(x^3+x^2-1)的值。A.0B.1C.∞D(zhuǎn).-∞9.已知函數(shù)f(x)=sin(x)+cos(x)，求f''(x)的值。A.-2sin(x)B.-2cos(x)C.2sin(x)D.2cos(x)10.計(jì)算下列極限lim(x→0)(tan(x)-sin(x))/x^3的值。A.1/2B.1/3C.1/6D.1/4二、填空題（每題4分，共20分）11.已知函數(shù)f(x)=x^2-4x+3，求f(x)的最小值。__________12.計(jì)算定積分∫(-1,1)|x|dx的值。__________13.已知等比數(shù)列{bn}的首項(xiàng)b1=8，公比q=1/2，求b4的值。__________14.計(jì)算下列極限lim(x→0)(e^x-1-x)/x^2的值。__________15.已知函數(shù)f(x)=ln(x)，求f'(x)的值。__________三、解答題（每題25分，共50分）16.求函數(shù)f(x)=x^3-6x^2+11x-6的極值點(diǎn)，并判斷極值點(diǎn)的性質(zhì)。17.解下列微分方程：y'+2y=e^(-2x)。答案一、選擇題1.A2.B3.A4.B5.A6.B7.D8.A9.B10.C二、填空題11.112.213.114.1/215.1/x三、解答題16.函數(shù)f(x)=x^3-6x^2+11x-6的導(dǎo)數(shù)為f'(x)=3x^2-12x+11。令f'(x)=0，解得x=1和x=3/3。通過(guò)二階導(dǎo)數(shù)測(cè)試，f''(x)=6x-12，f''(1)=-6<0，所以x=1是極大值點(diǎn)；f''(3/3)=0，所以x=3/3是拐點(diǎn)。17.微分方程y'+2y=e^(-2x)的積分因子為e^(2x)，兩邊乘以積分因子得e^(2x)