Evaluate a quantum kernel entry

Two classical samples $x,x'\in\mathbb R^2$ are encoded by the $R_X$ product encoding on two qubits,

$\lvert\phi(x)\rangle=R_X(x_0)\otimes R_X(x_1)\,\lvert00\rangle,\qquad R_X(\theta)=e^{-i\theta X/2}=\begin{pmatrix}\cos\frac\theta2&-i\sin\frac\theta2\\-i\sin\frac\theta2&\cos\frac\theta2\end{pmatrix}.$

Compute the fidelity kernel

$K(x,x')=\lvert\langle\phi(x)\vert\phi(x')\rangle\rvert^2\qquad\text{for}\qquad x=(0.3,\,1.2),\quad x'=(1.0,\,0.4).$

Enter a single real number. The answer is graded with absolute tolerance $10^{-3}$; you may also type an exact expression such as cos(0.35)^2*cos(0.4)^2.