(1)logaN^n=nlogaN求推导公式(2)已知a=lgx,则a+x等于?(3)若2.5^x=1000,0.25^y=1000,则(1/x)-(1/y)d\等于?(4)设函数f(x)=logax(a>0且a不等于0)若f(x1x2...x2010)=8,则f(x1^2)+f(x2^2)+f(x2010^2)的值等于第
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![(1)logaN^n=nlogaN求推导公式(2)已知a=lgx,则a+x等于?(3)若2.5^x=1000,0.25^y=1000,则(1/x)-(1/y)d\等于?(4)设函数f(x)=logax(a>0且a不等于0)若f(x1x2...x2010)=8,则f(x1^2)+f(x2^2)+f(x2010^2)的值等于第](/uploads/image/z/2688261-69-1.jpg?t=%EF%BC%881%EF%BC%89logaN%5En%3DnlogaN%E6%B1%82%E6%8E%A8%E5%AF%BC%E5%85%AC%E5%BC%8F%EF%BC%882%EF%BC%89%E5%B7%B2%E7%9F%A5a%3Dlgx%2C%E5%88%99a%2Bx%E7%AD%89%E4%BA%8E%3F%EF%BC%883%EF%BC%89%E8%8B%A52.5%5Ex%3D1000%2C0.25%5Ey%3D1000%2C%E5%88%99%281%2Fx%29-%281%2Fy%29d%5C%E7%AD%89%E4%BA%8E%3F%EF%BC%884%EF%BC%89%E8%AE%BE%E5%87%BD%E6%95%B0f%EF%BC%88x%EF%BC%89%3Dlogax%EF%BC%88a%3E0%E4%B8%94a%E4%B8%8D%E7%AD%89%E4%BA%8E0%EF%BC%89%E8%8B%A5f%EF%BC%88x1x2...x2010%EF%BC%89%3D8%2C%E5%88%99f%EF%BC%88x1%5E2%EF%BC%89%2Bf%28x2%5E2%29%2Bf%28x2010%5E2%29%E7%9A%84%E5%80%BC%E7%AD%89%E4%BA%8E%E7%AC%AC)
(1)logaN^n=nlogaN求推导公式(2)已知a=lgx,则a+x等于?(3)若2.5^x=1000,0.25^y=1000,则(1/x)-(1/y)d\等于?(4)设函数f(x)=logax(a>0且a不等于0)若f(x1x2...x2010)=8,则f(x1^2)+f(x2^2)+f(x2010^2)的值等于第
(1)logaN^n=nlogaN
求推导公式
(2)已知a=lgx,则a+x等于?
(3)若2.5^x=1000,0.25^y=1000,则(1/x)-(1/y)d\等于?
(4)设函数f(x)=logax(a>0且a不等于0)若f(x1x2...x2010)=8,则f(x1^2)+f(x2^2)+f(x2010^2)的值等于
第二题错了
改(2)已知a=lgx,则a+3等于?
(1)logaN^n=nlogaN求推导公式(2)已知a=lgx,则a+x等于?(3)若2.5^x=1000,0.25^y=1000,则(1/x)-(1/y)d\等于?(4)设函数f(x)=logax(a>0且a不等于0)若f(x1x2...x2010)=8,则f(x1^2)+f(x2^2)+f(x2010^2)的值等于第
(1)logaN^n=nlogaN
推导公式:
由对数加法公式:logaM+logaN=logaMN,
n个logaN相加得
logaN+ logaN+…+logaN
=loga(N×N×…×N) (n个N相乘)
=logaN^n;
(2)已知a=lgx,则a+3等于?
a+3=lgx+3=lgx+lg1000=lg1000x;
(3)若2.5^x=1000,0.25^y=1000,则(1/x)-(1/y)等于?
∵2.5^x=1000,
∴x=log1000,1/x=log2.5=(lg2.5)/3
(表示底数是2.5,其他类似)
∵0.25^y=1000,
∴y=log1000,1/y=log0.25=(lg0.25)/3
(1/x)-(1/y)= (lg2.5)/3 - (lg0.25)/3=[(lg2.5) - (lg0.25)]/3=(lg10)/3=1/3;
(4)设函数f(x)=logax(a>0且a不等于0),若f(x1x2…x2010)=8,
则f(x1²)+f(x2²)+…+f(x2010²)的值等于?
∵f(x1x2…x2010)=8,
∴log( x1x2…x2010)=8,
即logx1+logx2+…+logx2010=8
f(x1²)+f(x2²)+…+f(x2010²)
= logx1²+logx2²+…+logx2010²
=2 logx1+2logx2+…+2logx2010
=2 (logx1+logx2+…+logx2010)
=2×8
=16.