If x tends to 0, (1-ax ^ 2) ^ 1 / 4 and xsinx are equivalent infinitesimals, find a

If x tends to 0, (1-ax ^ 2) ^ 1 / 4 and xsinx are equivalent infinitesimals, find a

F (x) / g (x) uses lobita's law to seek up and down derivatives
(1-cosx) / (anx ^ n-1)
Continue derivation up and down
sinx/(an(n-1)x^n-2)
When X - & gt; 0, SiNx ~ x is equivalent to infinitesimal, SiNx is replaced by X
x/(an(n-1)x^n-2)
About X
1/(an(n-1)x^n-3) = 1
So n-3 = 0, n = 3
an(n-1)=1 a=1/6