Question

how did this expansion become like this?

Answer 1

which line you didnt get ?

Answer 2

the first one in the solutioin how did they simplify the term within bracket?

Answer 3

1+x+x^2 + x^3 = (1+x) + x^2( 1+x) = (1+x)(1+x^2)

was i able to clarify ?

Answer 4

omg....thank u! i was confused with synthetic division.........one more help...

Answer 5

is synthetic division(trial and error ) applicable only for equations? like x^3+x^2+x+1=0?

Answer 6

didnt get your query ? come again ?

Answer 7

in general are we allowed to equate the expression to 0 in order to find its factors?

Answer 8

if u see here there is no rhs cani equate it to 0 (not for this one) in general some complicated expression