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<div style="font-size:30px">'''WEIBULL(x,alpha,beta,lv)'''</div><br/>
*<math>x </math> is the value of the function.
*<math>alpha </math> and <math> beta </math> are the parameter of the distribution.
*<math>lv</math>is the logical value.
==Description==
*This function gives the value of the weibull distribution with 2-parameters.
*It is a continuous probability distribution.
*Weibull distribution also called Rosin Rammler distribution.
*It is used to model the lifetime of technical devices and is used to describe the particle size distribution of particles generated by grinding, milling and crushing operations.
*This distribution is closely related to the lognormal distribution.
*In WEIBULL(x,alpha,beta,lv),x is the value to evaluate the function.
*alpha is the shape parameter of the distribution.beta is the scale parameter of the distribution.
*lv is the logical value which determines the form of the distribution.
*When lv is TRUE, this function gives the value of the cumulative distribution. When lv is FALSE, then this function gives the value of the probability density function.
*When we are not omitting the value of lv, then it consider as FALSE.
*Weibull distribution is of two type :3-parameter weibull distribution and 2-parameter weibull distribution.
*This function gives the value of 2-parameter weibull distribution by setting the third parameter (location parameter) is zero.
*Also if alpha<1,then the failure rate of the device decreases over time.
*If alpha=1, then the failure rate of the device is constant over time.
*If alpha>1, then the failure rate of the device increases over time.
*The equation for cumulative distribution function is: <math>F(x,\alpha,\beta) = 1-e^{-(\frac{x}{\beta})}^\alpha</math>.
*The equation for probability density function is:
<math>f(x,\alpha,\beta) = \frac{\alpha}{\beta^\alpha}.x^{\alpha-1}.e^{-(\frac{x}{\beta})}^\alpha.</math>
*When alpha =1, then this function gives the exponentail with λ=1/β.
*This function gives the result as error when
1. Any one of the argument is non-numeric.
2. x is negative.
3.alpha<math>\le 0</math> or beta <math>\le 0.
WEIBULL(x,alpha,beta,lv), where , and , and .
<div id="6SpaceContent" class="zcontent" align="left">
<div id="6SpaceContent" class="zcontent" align="left">
<font color="#484848"><font face="Arial, sans-serif"><font size="2">110</font></font></font>
<font color="#484848"><font face="Arial, sans-serif"><font size="2">110</font></font></font>
<font color="#484848"><font face="Arial, sans-serif"><font size="2"><nowiki>=WEIBULL(B2,B3,B4,TRUE) is 0.088 and</nowiki></font></font></font>
<font color="#484848"><font face="Arial, sans-serif"><font size="2">UNIQ686c29c343f4309c-nowiki-00000004-QINU</font></font></font>
<font color="#484848"><font face="Arial, sans-serif"><font size="2"><nowiki>=WEIBULL(B2,B3,B4,FALSE) is 0.021</nowiki></font></font></font>
<font color="#484848"><font face="Arial, sans-serif"><font size="2">UNIQ686c29c343f4309c-nowiki-00000005-QINU</font></font></font>
</div>
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