Chapter 7 Trigonometry and Modelling (Year 2) Flashcards
1
Q
What is the formula for sin2A?
A
Sin2A = 2sinAcosA
2
Q
What is the formula for cos2A?
A
Cos^2A - sin^2A
3
Q
What is the formula for tan2A?
A
Tan2A = 2tanA / 1 - tan^2A
4
Q
How do you simplify expressions of the form acos theta + bsin theta?
A
Rsin(x + alpha)
Rcos(x - alpha)
R = sqrt(a^2 + b^2)
Alpha = arctan(b/a)
