Question

calcule : urgente
b-) (c3+4c2+c). (c-1)
c-) (2x+y). (x-y)
d-) ( xy-7). (xy+6)

Answer 1

b-) (c3+4c2+c). (c-1) = c4 + 4c3 + c2 - c3 - 4c2 - c ==> c4 + 3c3 - 3c2 - c

c-) (2x+y). (x-y) = 2x3 - 2xy + xy - y2 ==> 2x3 - xy - y2

d-) ( xy-7). (xy+6) = x2y2 + 6xy - 7xy - 42 ==> x2y2 - xy - 42