论文部分内容阅读
试题1(重庆卷,理科第7题)与向量 a=(7/2,1/2),b=(1/2,-7/2)的夹角相等,且模为1的向量是( ).A.(4/5,-3/5) B.(4/5,-(3/5))或(-(4/5),3/5) C.(2(2~(1/2)/3,-(1/3)) D.(2(2~(1/2)/3),-1/3)或(-2(2~(1/2))/3,1/3)试题特点:本题涉及单位向量、共线向量、向量的夹角等知识,解题的入口较宽,可从方程、解析几何、复数及向量运算的几何意义等角度入手,对训练学生思维的广阔性有价值.思路分析:
Question 1 (Chongqing volume, Science Question 7) is equal to the angle a = (7/2, 1/2), b = (1/2, -7/2) and the modulo 1 is ( (4/5, - 3/5) B. (4/5, - (3/5)) or (- (4/5), 3/5) C. (2 / 2/3, - 1/3)) D. (2 (1/2 to 1/2) / 3), -1 / 3 or -2 (1/2 to 1/2) / 3, 1/3) questions features: This question involves unit vectors, collinear vectors, vector angle and other knowledge, the problem-solving wide entrance, from the equation, analytic geometry, complex numbers and the vector operation of the geometric meaning of the point of view, training The broadness of the thinking of students valuable. Analysis of ideas: