Why does my child get a tiny number when finding an angle?
Your child uses sin instead of sin⁻¹ to find an angle, such as sin(0.5) instead of sin⁻¹(0.5) = 30°.
Why children do it
To find a side, children press sin, cos or tan, so they press the same key to find an angle. But that gives a ratio, not an angle. To go from the ratio back to the angle, it's the inverse: sin⁻¹, usually shift then sin. If sin θ = 0.5, θ = sin⁻¹(0.5) = 30°.
How to help at home
Ask them what they're finding: an angle needs sin⁻¹, cos⁻¹ or tan⁻¹ (shift, then sin).
The right way
Find the angle θ, to 1 decimal place.
- 36.9tan θ = 3 ÷ 4 = 0.75, and tan⁻¹(0.75) = 36.86...°, which is 36.9°.
Find out where your child is
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