What does that say?
I dont know if that's the correct terminology, but I can't find a basic tutorial on solving something like this:
How would you expand that, and can you explain how you knew/what model you used?
Ah okay, . Ignore the -5 at the front for now. Expanding , you would get .
Notice the descending powers on the first term and the ascending powers of the second term . The coefficients of each term (i.e. 1, 3, 3, 1) come from the 4th line of Pascal's triangle, if you know what that is.
Or, the coefficient of the first term in an expansion like this is always
is the power of the bracket, so in your case, . The second coefficient is . This goes on up until .
The first one comes from
Second one from
Third one from
And fourth one from
Then finally, you just multiply each of the terms by that we left out to finally get
Hope that helps and it's not too much of a wordy explanation. Feel free to reply with any more Qs