Without actually calculating the cubes, find the value of:

(i).


(ii). (0.2)3− (0.3)3 + (0.1)3


(i)


Let a =1/2, b=1/3and c= −5/6




=0/6


= 0


(1/2)3 + (1/3)3 + (5/6)3


= 3 (1/2) (1/3) (−5/6)


= −5/12


[a3 + b3 + c3–3abc =(a + b + c)(a2 + b2 + c2 ab bc−ca)]


[ if

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