1. **Problem statement:** We need to find the length of segment $AB$ in a triangular prism where $FE=8$ cm, $EC=14$ cm, the angle at vertex $F$ between edges $FA$ and $FB$ is $23^\circ$, and there is a right angle at vertex $A$ between edges $AF$ and $AB$.
2. **Understanding the geometry:** Since $AB$ is perpendicular to $AF$ at $A$, triangle $AFB$ is a right triangle with right angle at $A$.
3. **Using the angle at $F$:** The angle between $FA$ and $FB$ is $23^\circ$. Since $AB$ is perpendicular to $AF$, $AB$ is opposite the $23^\circ$ angle in triangle $AFB$.
4. **Applying trigonometry:** In right triangle $AFB$, $AB$ is opposite the $23^\circ$ angle, and $FB$ is the hypotenuse. We use the sine function:
$$\sin(23^\circ) = \frac{AB}{FB}$$
5. **Finding $FB$:** The length $FB$ corresponds to the edge $FE$ which is $8$ cm (assuming $FB=FE$ as per prism edges).
6. **Calculate $AB$:**
$$AB = FB \times \sin(23^\circ) = 8 \times \sin(23^\circ)$$
7. **Evaluate sine:**
$$\sin(23^\circ) \approx 0.3907$$
8. **Final calculation:**
$$AB = 8 \times 0.3907 = 3.1256$$
9. **Rounding to 2 decimal places:**
$$AB \approx 3.13$$
**Answer:** The length of $AB$ is approximately $3.13$ cm.
Length Ab 409791
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