Find the value using formula :
(i) $(1)^{3}$ + $(2)^{3}$
(ii) $(8)^{3}$ + $(15)^{3}$
(iii) $(19)^{3}$ + $(15)^{3}$

Open in App

Solution

We know, $a^{3} + b^{3} = (a + b) (a^{2} + b^{2} - a b)$
$(i) (1)^{3} + (2)^{3} = 3 (1 + 4 - 2) = 9$
$(i i) (8)^{3} + (15)^{3} = 23 (64 + 225 - 120) = 3887$
$(i i i) (19)^{3} + (15)^{3} = 34 (361 + 225 - 285) = 10234$

Suggest Corrections

Similar questions

Evaluate :
(i) $(8)^{3}$ (ii) $(15)^{3}$ (iii) $(21)^{3}$ (iv) $(60)^{3}$

(1^{3} + 2^{3} + 3^{3} + . . . . . . . 15^{3}) - (1 + 2 + 3 + . . . 15)

{(- 15)}^{3} + 7^{3} + 8^{3}

15^{3}

(- 4)^{3}

(1.2)^{3}

{(\frac{- 3}{4})}^{3}

The sum of $1^{3}$ + $2^{3}$ + $3^{3}$ + $4^{3}$ + ........... + $15^{3}$ is

Join BYJU'S Learning Program