Question

a-b=-10 and ab =-6 find the value of a3-b3

Answer 1

Solution:

/* x³-y³ = (x-y)³+3xy(x-y) */

It is given that,

a-b = -10 -----(1)

ab = -6 -----(2)

Now ,

a³-b³ = (a-b)³+3ab(a-b)

= (-10)³+3×(-6)×(-10)

/* from (1)&(2) */

= -1000 + 180

= -820

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