Question

Find : a3 +1/a3 if a + 1/a = 5.​

Answer 1

Answer:

110

Step-by-step explanation:

$(a+b)^{3} =a^{3} +b^{3} +3ab(a+b)$

∴$(a+\frac{1}{a})^{3}=a^{3}+\frac{1}{a^{3}} +3(a+\frac{1}{a} )$

=(5)³=a³+1/a³+3(5)

125-15=a³+1/a³

a³+1/a³=110

Hope this helps.