Transformations of Products into sum or difference and vice versa

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Analytical Geometry
Circles Equation given center and radius given ends of diameter General equation finding center and radius Standard forms of equations of Parabola Standard forms of equations of Ellipse Standard forms of equations of Hyperbola simple properties
Complex numbers
modulus and conjugate Arithmetic operations on complex number Modulus Amplitude form (Polar form) Euler form (exponential form) Properties De Movire’s Theorem and its applications
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Diffrentiation and it's Applications
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Integration and Its Applications
Indefinite Integral Standard forms Integration by decomposition of the integrand of trigonometric algebraic exponential logarithmic and Hyperbolic functions Integration by substitution Integration of reducible and irreducible quadratic factors Integration by part Definite Integrals and properties Definite Integral as the limit of a sum Application of Integration to find areas under plane curves and volumes of Solids of revolution Mean and RMS value
Matrices
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Partial fractions
Resolving a given rational function into partial fractions.
TRIGONOMETRY
Properties of Trigonometric functions Ratios of compound angles Multiple angles Sub multiple angles Transformations of Products into sum or difference and vice versa Simple trigonometric equations Properties of triangles Inverse Trigonometric functions
The formula for sin A * sin B in terms of sum and difference is:
A
1/2 [cos(A - B) - cos(A + B)]
B
1/2 [cos(A + B) + cos(A - B)]
C
1/2 [sin(A + B) + sin(A - B)]
D
1/2 [sin(A - B) - sin(A + B)]
Analysis & Theory

sin A * sin B = 1/2 [cos(A - B) - cos(A + B)] is the product-to-sum formula.