恩施中考数学试题及答案
一、单项选择题(每题2分,共10题)
1.计算:\(-2+3\)的结果是()
A.\(-1\)B.\(1\)C.\(-5\)D.\(5\)
2.函数\(y=\frac{1}{x-2}\)中,自变量\(x\)的取值范围是()
A.\(x\neq0\)B.\(x\neq2\)C.\(x\gt2\)D.\(x\geq2\)
3.下列运算正确的是()
A.\(a^2\cdota^3=a^6\)B.\((a^2)^3=a^5\)C.\(a^6\diva^2=a^4\)D.\((ab)^3=ab^3\)
4.已知一元二次方程\(x^2-4x+3=0\)的两根为\(x_1\),\(x_2\),则\(x_1+x_2\)的值为()
A.\(4\)B.\(-4\)C.\(3\)D.\(-3\)
5.一个多边形的内角和是\(720^{\circ}\),这个多边形是()
A.四边形B.五边形C.六边形D.八边形
6.如图,\(AB\)是\(\odotO\)的直径,\(\angleC=30^{\circ}\),则\(\angleABD\)等于()
A.\(30^{\circ}\)B.\(40^{\circ}\)C.\(50^{\circ}\)D.\(60^{\circ}\)
7.一次函数\(y=kx+b\)的图象经过点\((1,2)\)和\((0,3)\),则\(k\),\(b\)的值分别为()
A.\(k=-1\),\(b=3\)B.\(k=1\),\(b=3\)C.\(k=-1\),\(b=-3\)D.\(k=1\),\(b=-3\)
8.化简\(\frac{x^2-1}{x}\div\frac{x-1}{x^2}\)的结果是()
A.\(x(x+1)\)B.\(x(x-1)\)C.\((x+1)(x-1)\)D.\(x+1\)
9.已知点\(A(x_1,y_1)\),\(B(x_2,y_2)\)在反比例函数\(y=\frac{k}{x}(k\neq0)\)的图象上,若\(x_1\ltx_2\lt0\),\(y_1\lty_2\),则\(k\)的取值范围是()
A.\(k\gt0\)B.\(k\lt0\)C.\(k\geq0\)D.\(k\leq0\)
10.如图,在\(Rt\triangleABC\)中,\(\angleC=90^{\circ}\),\(AC=4\),\(BC=3\),则\(\sinA\)的值为()
A.\(\frac{3}{4}\)B.\(\frac{4}{3}\)C.\(\frac{3}{5}\)D.\(\frac{4}{5}\)
二、多项选择题(每题2分,共10题)
1.下列图形中,是轴对称图形的有()
A.线段B.角C.等腰三角形D.平行四边形
2.下列数据中,是近似数的有()
A.小明身高约\(165cm\)B.初一(1)班有\(45\)名学生
C.珠穆朗玛峰高出海平面约\(8848m\)D.数学课本有\(206\)页
3.下列函数中,\(y\)随\(x\)的增大而减小的有()
A.\(y=-2x+1\)B.\(y=\frac{3}{x}(x\gt0)\)C.\(y=-x^2+2x-1(x\gt1)\)D.\(y=3x-2\)
4.一个几何体的三视图如图所示,则这个几何体可能是()
A.圆柱B.圆锥C.三棱柱D.长方体
5.下列方程中,有实数根的是()
A.\(x^2+1=0\)B.\(x^2-2x+1=0\)C.\(x^2-x+1=0\)D.\(x^2-2x-1=0\)
6.已知\(a\),\(b\),\(c\)是\(\triangleABC\)的三边,且满足\(a^2+b^2+c^2=ab+bc+ca\),则\(\triangleABC\)是()
A.直角三角形B