In a triangle ABC, angle C is 90, CH is the height, BC = 10, CH = 3√11. Find sin A.

1. Calculate the length of the HВ segment:

BH = √BC² – CH² (by the Pythagorean theorem).

HВ = √10² – (3√11) ² = √100 – 99 = 1 unit.

2. We calculate the length of the segment AH:

AH x BH = CH² (according to the properties of a right-angled triangle).

AH = CH²: BH = 99: 1 = 99 units.

3. AB = 99 + 1 = 100 units of measurement.

4. Sine ∠A = BC: AB = 10: 100 = 0.1.

Answer: sine ∠A is equal to 0.1.



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