Question

给出四个函数图象分别满足：①f(x＋y)＝f(x)＋f(y)；②g(x＋y)＝g(x)·g(y)；③u(x·y)＝u(x)＋u(y)；④v(x·y)＝v(x)·v(y)．与下列函数图象对应的是(　　)

A．①—a，②—d，③—c，④—b

B．①—b，②—c，③—a，④—d

C．①—c，②—a，③—b，④—d

D．①—d，②—a，③—b，④—c

Answer 1

 [答案]　D

[解析]　显然满足①f(x＋y)＝f(x)＋f(y)的函数应是y＝kx这种类型，故对应的图象应是d；满足②g(x＋y)＝g(x)·g(y)应该是指数函数，故对应的图象应是a；满足③u(x·y)＝u(x)＋u(y)的应是对数函数，故对应的图象应是b；满足④v(x·y)＝v(x)·v(y)的应是幂函数y＝xⁿ，故对应的图象应是c.