Auto rearrange math formulas

[donkeycrusher]

I've searched for about 4 hours now, so I finally have to break down and ask.

I'm creating an excel spreadsheet for physics (very fun) and thus far, doing it the hard way. For each equation, I've been using the =if(and(ifblank))) functions and rewriting my formulas for each scenario of blank or unknown cells. This has been a real PAIN IN THE REAR END!. Below is an example of what I have done (the hard way) with regard to right angles.

A1="Adjacent" B1="Opposite" C1="Hypotenuse" D1=Theta

A2=IF(AND(ISBLANK(A7),ISBLANK(B7)),COS(RADIANS(D7))*C7,IF(AND(ISBLANK(A7),ISBLANK(C7)),B7/TAN(RADIANS(D7)),IF(AND(ISBLANK(A7),ISBLANK(D7)),SQRT(C7^2-B7^2),"")))

B2=IF(AND(ISBLANK(B7),ISBLANK(D7)),SQRT(C7^2-A7^2),IF(AND(ISBLANK(B7),ISBLANK(A7)),SIN(RADIANS(D7))*C7,IF(AND(ISBLANK(B7),ISBLANK(C7)),TAN(RADIANS(D7))*A7,"")))

C2=IF(AND(ISBLANK(C7),ISBLANK(A7)),B7/SIN(RADIANS(D7)),IF(AND(ISBLANK(C7),ISBLANK(B7)),A7/COS(RADIANS(D7)),IF(AND(ISBLANK(C7),ISBLANK(D7)),SQRT(A7^2+B7^2),"")))

D2==IF(AND(ISBLANK(D7),ISBLANK(A7)),DEGREES(ASIN(B7/C7)),IF(AND(ISBLANK(D7),ISBLANK(B7)),DEGREES(ACOS(A7/C7)),IF(AND(ISBLANK(D7),ISBLANK(C7)),DEGREES(ATAN(B7/A7)),"")))


Now that I've tortured myself the hard way, I'm hoping someone can tell me how to simply write a formula that basically goes
=sqrt(A1^2 + B1^2 = C1^2)
Then automatically rearranges the equation so that if I have any combination of the two legs, it automatically solves for the other.

Thanks in advance for the help and reading this lenghthy post.

 

[JimM]

Does this do what you want ??

=IF(OR(A1=0,B1=0),SQRT(C1^2-B1^2-A1^2),SQRT(A1^2+B1^2))