Arbitrary Triangle and Its Interior Angles
2017-10-30 10:22
This GeoGebra example demonstrates the construction of an arbitrary triangle and its interior angles. Using Segment and Angle commands, it dynamically builds the vertices and sides, displaying the three interior angles in real-time. It helps intuitively understand the geometric properties and angle sum theorem of any triangle for basic geometry teaching.
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<scripting blocked="false" disabled="false"/>
<construction title="任意三角形" author="" date="">
<element type="point" label="A">
<show object="true" label="true" ev="4"/>
<objColor r="0" g="0" b="255" alpha="0"/>
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<coords x="10.42" y="5.2" z="1"/>
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<command name="Segment">
<input a0="A" a1="B"/>
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<command name="Segment">
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<command name="Angle">
<input a0="A" a1="C" a2="B"/>
<output a0="α"/>
</command>
<element type="angle" label="α">
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</element>
<command name="Angle">
<input a0="C" a1="B" a2="A"/>
<output a0="β"/>
</command>
<element type="angle" label="β">
<angleStyle val="0"/>
<value val="0.6907268703342954"/>
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<cellPair>
<inputCell>
<expression value="Angle[C, B, A]+Angle[A, C, B]" eval="Evaluate(Angle(C,B,A) + Angle(A,C,B))" evalCmd=""/>
</inputCell>
<outputCell>
<expression value="asin(17501 / sqrt(21222097130)) + acos(174970 / sqrt(51530313029)) + (1 / 2 * π)" native="true"/>
</outputCell>
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