# Tutor profile: Jay E.

## Questions

### Subject: Trigonometry

What is the periodicity of sin(x), sin(2x), and sin(3x)

Sin(x), representing the most general form of "sin" functions, repeats every 2pi (i.e. when x starts from 0 to 2pi). Sin(2x) repeats every 0 to pi. (from (2pi)/2 --> the denominator comes from the coefficient of x) Thus, Sin(3x) repeats every 0 to 2pi/3.

### Subject: Calculus

Find the equation of the plane that passes through the point (1,3,2) and contains the vector v = i+j+k and w=3i+k.

N = v x w (cross product) N = i + 2j -3k Equation for the plane: A(x-x0) + B(y-y0) + C(z-z0) = 0 1(x-1) + 2(y-3) -3 (z-2) = 0 Final answer: x+2y-3z=1

### Subject: Statistics

The number of students attending a class has a poisson distribution with Lambda = 100. What is the probability of 120 or more student attendance?

Suppose: X: number of students attending Miu_x: 100 Sigma_x_square: 100 If X ~ Poission (Lambda) P (X >= 120) = P (z >=2) = 1 - P (Z<2) = .03

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