Question

\mathrm{a}_{\mathrm{n}}=\int_{0}^{\frac{\pi}{2}} \frac{1-\cos 2 \mathrm{nx}}{1-\cos \mathrm{x}} \mathrm{dx},a
n
​ =∫
0
2
π
​
​
1−cosx
1−cos2nx
​ dx, then \mathrm{f}(\mathrm{x})=\left|\begin{array}{lll}\mathrm{a}_{1} & \mathrm{a}_{2} & \mathrm{a}_{3} \\ \mathrm{a}_{4} & \mathrm{a}_{5} & \mathrm{a}_{6} \\ \mathrm{a}_{7} & \mathrm{a}_{8} & \mathrm{a}_{9}\end{array}\right| \forall \mathrm{x} \in \mathrm{R} ;f(x)=
∣
∣
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​
a
1
​
a
4
​
a
7
​
​
a
2
​
a
5
​
a
8
​
​
a
3
​
a
6
​
a
9
​
​
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​ ∀x∈R; then \mathrm{f}(1)=f(1)=

Answer 1

$<marquee> <strong><em><u>u dont know coadings xd!</u></em></strong></p><p>$