Casio FX-9750G, FX-9860GII ILogarithmic Regression Graph, IExponential Regression Graph, y = a·bx, y = a·ebx, y = ax2 + bx + c, (aeˆbx) or (abˆx), y = ax3 + bx2 + cx + d

Quadratic regression			Cubic regression
Model formula.......		y = ax2 + bx + c	Model formula.......		y = ax3 + bx2 + cx + d
a..........	regression second coefficient		a..........	regression third coefficient
b..........	regression first coefficient		b..........	regression second coefficient
c..........	regression constant term		c..........	regression first coefficient
	(y-intercept)		d	regression constant term
				(y-intercept)
Quartic regression
Model formula.......		y = ax4 + bx3 + cx2 + dx + e
a..........	regression fourth coefficient
b..........	regression third coefficient
c..........	regression second coefficient
d..........	regression first coefficient
e..........	regression constant term (y-intercept)

ILogarithmic Regression Graph

Logarithmic regression expresses y as a logarithmic function of x. The standard logarithmic regression formula is y = a + b × In x, so if we say that X = In x, the formula corresponds to linear regression formula y = a + bX.

(CALC)(E)(Log)

(DRAW)

The following is the logarithmic regression model formula.

y = a + b·ln x

a..............	regression constant term
b..............	regression coefficient

IExponential Regression Graph

Exponential regression expresses y as a proportion of the exponential function of x. The standard exponential regression formula is y = a × ebx, so if we take the logarithms of both sides we get In y = In a + bx. Next, if we say Y = In y, and A = In a, the formula corresponds to linear regression formula Y = A + bx.

(CALC)(E)(Exp)

(aeˆbx) or (abˆx)

(DRAW)

The following is the exponential regression model formula.

y = a·ebx

a..............	regression coefficient
b..............	regression constant term
y = a·bx
a..............	regression constant term
b..............	regression coefficient

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