Jan 07 2021 07:01 AM
Hi, Can someone please create an excel formula for the follow equations:
Jan 07 2021 08:13 AM
Let's say you enter the values for a, b, c and h in B1, B2, B3 and B4, respectively.
In another cell, say B5, enter the formula
=B4/4*SQRT((B1+B2+B3)*(B2+B3-B1)*(B3+B1-B2)*(B1+B2-B3))
or
=B4/4*SQRT(-B1^2+2*(B1*B2)^2+2*(B1*B3)^2-B2^2+2*(B2*B3)^2-B3^2)
Jan 08 2021 06:09 AM
I would like to simplify the expression.
Suppose a, b, c, h are inputted in B1, B2, B3, B4.
Then in B5, input the formula "=SUM(B1:B3)"
In order to find the volume, you may consider the following formula:
=(B4/4)*SQRT(B5*(B5-2*B1)*(B5-2*B2)*(B5-2*B3))
Jan 08 2021 06:22 AM
@Man Fai Chan Your formula worked! Thanks!
Jan 08 2021 08:15 AM - edited Jan 09 2021 10:46 AM
=B4/4*SQRT(-B1^2+2*(B1*B2)^2+2*(B1*B3)^2-B2^2+2*(B2*B3)^2-B3^2)
Incorrect. Three typos and a translation mistake. Errata:
=B4/4*SQRT(-(B1^4)+2*(B1*B2)^2+2*(B1*B3)^2-B2^4+2*(B2*B3)^2-B3^4)
Note: In Excel, -B1^4 is parsed as (-B1)^4, which is always positive. But in math, it is parsed as -(B1^4), which is always negative.
PS.... In selecting a, b and c, we must avoid SQRT returning #NUM because its parameter is negative. An online calculate [*] specifies the following requirements:
a+b > c
a+c > b
b+c > a
One set of values that meets those conditions:
a: 123
b: 456
c: 543
[*] online calculator (click here)