Eric Nicholas K's answer to Kathy's Secondary 4 A Maths Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
4417 answers (Tutor Details)
The 'b' can be replaced with 'x' if that makes things look more familiar.

If the degree (power of x, or in this case, b) of the first term is lower than the degree (power of x, or b in this case) of the second term, your expansion will appear in ascending powers.