Hello Mathematics Community, currently I am trying to prove:  $(\sum_{i=1}^{n+1}i)^2 = \sum_{i=1}^{n}i^3$  by Induction.  My Progress:  Assumption: $(\sum_{i=1}^{n+1}i)^2 = \sum_{i=1}^{n}i^3$  Induction Hypothesis: $=(\sum_{i=1}^{n+1}i)^2 = \sum_{i=1}^{n+1}i^3$  Induction Step:  $(\sum_{i=1}^{n}i)^2 = \sum_{i=1}^{n}i^3$  $=(\sum_{i=1}^{n+1}i)^2 = \sum_{i=1}^{n+1}i^3$  $=(\sum_{i=1}^{n} i + \sum_{i=n+1}^{n+1} i)^2$  But how can I use my Assumption here ?  It is important that I want to prove this with the summation symbol and not with the closed-form equations.  sincerely, M.Hisoka
How can I prove that     $$1^3+ 2^3 + \cdots + n^3 = \left(\frac{n(n+1)}{2}\right)^2$$    for all $n \in \mathbb{N}$? I am looking for a proof using mathematical induction.  Thanks
How do I pass parameter TO a Visualforce page from a link in an email? Here's what I am trying to do:  1) User creates record A.  2) Time-based workflow sends an email to the Record A creator based on a date field in the record.  3) The email template has a URL link.  4) The URL links to a Visualforce page that is basically a form with fields to be filled out (this Visualforce page is in a managed package) and a save button that creates a new User record.  5) When the User clicks the URL link in the email, the Visualforce page opens in a new window.  6) I would like to pass the values of the fields in record A to pre-fill the Visualforce page fields.   Here's my link:  &lt;a href="https://cs19.visual.force.com/apex/CloneThisUser?Desktop=true&amp;Id={!Pending_User__c.User_to_CloneId__c}&amp;formGroupInputSmall={!Pending_User__c.First_Name__c}   And here's the code from the relevant section of the Visualforce page:  &lt;div class="form-group form-group-sm"&gt;       &lt;!-- &lt;apex:outputLabel styleClass="col-sm-2 control-label" for="formGroupInputSmall"&gt;First Name&lt;/apex:outputLabel&gt; --&gt;       &lt;div class="col-xm-11 col-sm-12"&gt;           &lt;apex:inputField html-placeholder="First Name" styleClass="form-control FirstNameInput"  value="{!u.FirstName}" id="formGroupInputSmall"/&gt;       &lt;/div&gt;     &lt;/div&gt;   I have only included the first field I would like to pass the parameter to, in order to keep this post simple.   The link passes the User_to_Clone_Id__c just fine but does not fill in the "First Name" field with the value of the First_Name__c .  What am I doing incorrectly? Thanks. 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