maths formulae

• What is the quadratic formula?

  X=-b±√(b²−4ac)/2a
• When can you use the sine rule?

  The sine rule can be used to find an angle from SSA, AAS
• When can you use the cosine rule?

  The cosine rule can find a side from 2 sides and the included angle, or an angle from 3 sides.
• What is the sine rule?

  a/sinA = b/sinB = c/sinC
• What is the cosine rule?

  a^2 = b^2 + c^2 - 2bcCosA
• What is the cosine rule for an angle?

  cos A = (b^2 + c^2 - a^2) / 2bc