方程log3(π-1)=log9(x+5)的解是?
问题描述:
方程log3(π-1)=log9(x+5)的解是?
答
答:利用换底公式log3(π-1)=log9(x+5)log3(π-1)=log3(x+5)/log3(9)log3(π-1)=log3(x+5)/22log3(π-1)=log3(x+5)log3(π-1)²=log3(x+5)所以:x+5=(π-1)²所以:x=(π-1)²-5x=π²-2π-4...