delta V = (l + delta l)3 = 3l2delta l How did we arrive at 3l2delta l Please - Physics - Heat and Energy

Question

delta V = (l + delta l)3 = 3l2delta l
How did we arrive at 3l2delta l ? Please show the
working

Decoder_2 · Accepted Answer

delta V = (l + delta l)3 = 3l2delta l How did we arrive at 3l2delta l ? Please show the working.