解不等式log3(x^2-2x-3) <log3(x+7)大神们帮帮忙
问题描述:
解不等式log3(x^2-2x-3) <log3(x+7)大神们帮帮忙
答
因为log3 x是增函数而且x-2x-3>0且x+7>0所以(x+1)(x-3)>0且x>-7x3且x>-7-7