Question

9的a次方＝16的b方＝12 c＝1/a＋1/b函数f(x)＝c－3x方＋1

Answer 1

9^a=16^b=12

a=log9(12)

b=log16(12)

c=1/a+1/b=1/log9(12)+1/log16(12)=log12(9)+log12(16)=log12(9*16)=log12(12^2)=2

f(x)=t/(c^(-3x)+1)=t/(2^(-3x)+1)