Solve it using identity- 13- m 3- l 3- m 3

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Standard VII

Mathematics

(a+b)(a-b) Expansion and Visualisation

Solve it usin...

Question

Solve it using identity: $(l^{3} + m^{3}) (- l^{3} + m^{3})$

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Solution

$(l^{3} + m^{3}) (- l^{3} + m^{3}) = (m^{3} + l^{3}) (m^{3} - l^{3}) = (m^{3})^{2} - (l^{3})^{2} [U s i n g (a + b) (a - b) = a^{2} - b^{2}] = m^{6} - l^{6}$

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Solve it using identity: (l3+m3)(−l3+m3)

(l3+m3)(−l3+m3)=(m3+l3)(m3−l3)=(m3)2−(l3)2 [Using(a+b)(a−b)=a2−b2]=m6−l6

Solve it using identity: $(l^{3} + m^{3}) (- l^{3} + m^{3})$

$(l^{3} + m^{3}) (- l^{3} + m^{3}) = (m^{3} + l^{3}) (m^{3} - l^{3}) = (m^{3})^{2} - (l^{3})^{2} [U s i n g (a + b) (a - b) = a^{2} - b^{2}] = m^{6} - l^{6}$