Question

If a = 2+5 then find the value of at the

11th - 12th Class

Maths

Solution

4.0 (1 ratings)

( a=2+sqrt{3} ) ( a^{2}=4+3+4 sqrt{3} ) ( Rightarrow a^{2}+frac{1}{a^{2}}=7+4 sqrt{3}+frac{1}{7+4 sqrt{3}} ) ( Rightarrow a^{2}+frac{1}{a^{2}}=frac{(1+4 sqrt{3})^{2}+1}{7+4 sqrt{3}} ) ( Rightarrow a^{2}+frac{1}{a^{2}}=frac{49+48+56 sqrt{3}+1}{7+4 sqrt{3}} ) ( Rightarrow a^{2}+frac{1}{a^{2}}=frac{98+56 sqrt{3}}{7+4 sqrt{3}} ) ( Rightarrow a^{2}+frac{1}{a^{2}}=14left(frac{7+43}{7+43}right) ) ( Rightarrow a^{2}+frac{1}{a^{2}}=14 )