Log-linear transformation係DSE Maths Core好鍾意問嘅類型,可以話年年都有一條,MC同埋長題目(Section B)都問過。睇落好似好複雜,不過只要明白個操作,就會覺得好簡單。覺得難係因為書係完完全全冇教到。
By definition, log-linear transformation is the process of transforming
function [exponential function (y=abx) or power function (y=axn)] into linear
form by taking log.
簡單D講,log-linear transformation有兩個type(case)
Type 1 (Case 1): y=abx
Type 2 (Case 2): y= axn
個操作就係將左右take log, 之後將條式變到好似Equation of a Straight Line 咁。
首先你要知道咩係Equation of a Straight Line。在x-y coordinate plane 上嘅直線,都可以以Equation of a Straight Line(直線方程)去表達。
一般就係y=mx+c
‘y’: y-axis 表達嘅野
m: slope
‘x’: x-axis 表達嘅野
c: y-intercept
Type 2 (Case 2): y= axn
你會係幅圖搵到你要嘅野,例如slope/y-int.
有時會唔俾式你,要你由幅圖有嘅搵番條式。有時個log base唔係10,又可能直情俾兩個唔同嘅log base。當遇到就諗下啦。
DSE Past Paper
HKDSE
2012 Paper II Q32
HKDSE
2013 Paper II Q32