2U Math Q (1 Viewer)

[xibu34]

I get how to do the question, but how are you meant to know which stars to use for m1 and m2 ? The solutions use m1 and b1 for acrux, wouldn't it be m2 and b2 considering they introduced it into the problem second or am i tripping ?

 

[Sam14113]

As long as you use the same star for m2 and b2, you'll get the same answer. It's a nice fact about logs that so that means it works either way.

 

[ZakaryJayNicholls]

I get how to do the question, but how are you meant to know which stars to use for m1 and m2 ? The solutions use m1 and b1 for acrux, wouldn't it be m2 and b2 considering they introduced it into the problem second or am i tripping ?

View attachment 39657

As Sam correctly pointed out, as long as you have and both belonging to the same star it will work either way.

In terms of formal Astrophysics, it is not uncommon to turn the subscript 1 and 2 into the name of the stars so as to prevent confusion (as subscripts are used to name variables sharing a common base or letter anyway), so would become and would become . The same would hold for b's, so would become and would become .