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已知f(x)=4的x次方/4的x次方+2,则f(1/11)+f(2/11)+******+f(10/11)=?
题目详情
已知f(x)=4的x次方/4的x次方+2,则f(1/11)+f(2/11)+******+f(10/11)=?
▼优质解答
答案和解析
f(1-x)=4^(1-x)/(4^(1-x)+2)
=4/(4+2*4^x)
=2/(2+4^x)
f(x)+f(1-x)
=4^x/(4^x+2)+2/(4^x+2)
=(4^x+2)/(4^x+2)
=1
f(1/11)+f(2/11)+******+f(10/11)
=[f(1/11)+f(10/11)]+...+[f(5/11)+f(6/11)]
=1+1+1+1+1
=5
=4/(4+2*4^x)
=2/(2+4^x)
f(x)+f(1-x)
=4^x/(4^x+2)+2/(4^x+2)
=(4^x+2)/(4^x+2)
=1
f(1/11)+f(2/11)+******+f(10/11)
=[f(1/11)+f(10/11)]+...+[f(5/11)+f(6/11)]
=1+1+1+1+1
=5
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