It begryp oerflakte jout de mannichte fan in flakte oan dy't metten wurde kin mei help fan in flaktemjitte . In flak is in twadiminsjonaal objekt sûnder ynhâld dy't effen as bryk wêze kin.
objekt/figuer
ferklearring
oerflakte = A {\displaystyle =A\,} fjouwerhoeke
lingte fan de siden a {\displaystyle a\,}
A = a 2 {\displaystyle A=a^{2}\,} rjochthoeke
lingte x breedte a , b {\displaystyle a,\,b}
A = a ⋅ b {\displaystyle A=a\cdot b} trijehoeke
basis g {\displaystyle g\,} h {\displaystyle h\,}
A = g ⋅ h 2 {\displaystyle A={\frac {g\cdot h}{2}}} rûntsje
radius r {\displaystyle r\,}
A = π r 2 {\displaystyle A=\pi r^{2}\,} seishoeke
lingten a {\displaystyle a\,}
A = 3 2 a 2 3 {\displaystyle A={\frac {3}{2}}a^{2}{\sqrt {3}}} parallelogram
lingte fan de siden a {\displaystyle a\,}
A = a 2 {\displaystyle A=a^{2}\,} rút
diagonalen A C ¯ , B D ¯ {\displaystyle {\overline {AC}},{\overline {BD}}}
A = A C ¯ ⋅ B D ¯ 2 {\displaystyle A={\frac {{\overline {AC}}\cdot {\overline {BD}}}{2}}} trapezium
parallel lykoprinnende siden a , c {\displaystyle a,\,c} h {\displaystyle h\,} a {\displaystyle a\,} c {\displaystyle c\,}
A = a + c 2 ⋅ h {\displaystyle A={\frac {a+c}{2}}\cdot h}
objekt/figuer
ferklearring
oerflakte = A {\displaystyle =A\,} kubus
sydlingte a {\displaystyle a\,}
A = a ⋅ 6 {\displaystyle A=a\cdot 6} balke
lingte l {\displaystyle l\,} b {\displaystyle b\,} h {\displaystyle h\,}
A = 2 ( l ⋅ b + l ⋅ h + h ⋅ b ) {\displaystyle A=2(l\cdot b+l\cdot h+h\cdot b)} bol
pi π {\displaystyle \pi \,} r {\displaystyle r\,}
A = 4 ⋅ π ⋅ r 2 {\displaystyle A=4\cdot \pi \cdot r^{2}\,} silinder
pi π {\displaystyle \pi \,} r {\displaystyle r\,} h {\displaystyle h\,}
A = 2 π r ⋅ h {\displaystyle A=2\pi r\cdot h} kegel
radius r {\displaystyle r\,} π {\displaystyle \pi \,} h {\displaystyle h\,}
A = π r ( r + r 2 + h 2 ) {\displaystyle A=\pi r(r+{\sqrt {r^{2}+h^{2}}}\!)}
It kin ek brûkt wurde foar de boppeste laach as flak fan in beskaat objekt of foar de bûtenste flakken mei-inoar, it útwindige fan in lichem.
