# A question about mathematical writing

Let $V_A,V_B$ represent velocity quantity. How can I write the formula "$V_A^2-V_B^2$" as a mathematical expression? I think it can be written as "the difference between velocity squared $V_A$ and $V_B$". Is that true?

• How do you define $V_A^2$, is $V_A$ a vector? – Yujie Zha Jun 25 '17 at 15:41
• @YujieZha OP says that it is the magnitude of the velocity vector $\vec{V_A}$, and obviously we are working with real numbers. – onurcanbektas Jun 25 '17 at 15:44
• @ Yujie Zha and @Leth, $V_A$ is a real number. – like_math Jun 25 '17 at 15:47
• For a single object at two different times with constant accelration $a$, we have $V_1^2-V_0^2 = 2a\cdot\Delta s$. Is that worth something? – Arthur Jun 25 '17 at 15:48
• @ zhw, thank you, I think this is true. – like_math Jun 25 '17 at 16:11

"How can I write the formula "$V_A^2-V_B^2$" as a mathematical expression?" You just did. Perhaps your question is really "How can I write "$V_A^2-V_B^2$" in words?" I'm not sure why you would want to do that, but if I had to, I would write this: "the difference between the square of the velocity of $A$ and the square of the velocity of $B$."