Farsaingeachd triantain

Gus farsaingeachd triantain obrachadh a-mach, feumaidh fios a bhith agad air dà thaobh agus air a' cheàrn eatarra.

Farsaingeachd\,triantain = \frac{1}{2} \times ab \times \sin C

Eisimpleir

Lorg farsaingeachd an triantain ABC.

Diagram of triangle with 35° angle and values 3cm and 7cm

Farsaingeachd = \frac{1}{2} \times bc \times \sin A

Farsaingeachd = 0.5 \times 3 \times 7 \times \sin (35^\circ )

Farsaingeachd = 6.02255...

Farsaingeachd = 6.02\,c{m^2}\,(gu\,2\,id)

Question

Obraich a-mach farsaingeachdan an triantain ABC.

Triangle with 130 degree angle, sides of 5 and 8cm and lables of A, B and C

Farsaingeachd = \frac{1}{2} \times ac \times sinB

Farsaingeachd = 0.5 \times 8 \times 5 \times sin (130^\circ)

Farsaingeachd = 15.3\,{cm^2}\,(gu\,1\,id)