# triginometry

hi i tried solving this problem but i get the second part wrong? please help me. thanks you

question:
a) the maximum number of hours of sunlight is 15.3h, and occurs on June 21(day 172). The minimum number of hours of sunlight is 9.1h, and occurs on december 21(day 355). use this information. Determine the period,amplitude,phase shift, and vertical displacement.
Amplitude=max-min/2
=15.3h-(+9.1h)/2
=3.1
Period= 2pi/b
=2pi/365 (b=one cycle, number of days in a year.

Phase shift= moved to day 172 when the first day is given so this is our pahse shift. phase shift=172

vertical displacement = max+min/2
=15.3+(+9.2)/2
=12.3
t= asin2pi/b(n-b)+c
t=3.1sin2pi/365(n-172)+ 12.3
*note Pi=180

b) Determine a day when there are 14h of sunlight.
i subbed in this value with t= 14 but i got a very small number and i have a graph which does not support this. how do i correctly do this? thank you

1. 👍 0
2. 👎 0
3. 👁 299
1. Pi is not 180. PI should be 3.141592 in that equation.

14= 3.1sin (2PI/365 *(n-172)) + 12.3
1.7=3.1 sin(2PI/365 ((n-172))

2PI/365 (n-172)= arcsin1.7/3.1

n-172=33.7
n=206

check my work.

1. 👍 0
2. 👎 0
👨‍🏫
bobpursley

## Similar Questions

1. ### chem class

What is the pH of an aqueous solution at 25.0 °C that contains 3.98 × 10-9 M hydroxide ion? i posted this before and i tried solving it but i get it wrong 14 = ph + - log (3.98 × 10-9) 14- 8.4 = ph 5.6 = ph but the correct

2. ### Buffer solution

Solve an equilibrium problem (using an ICE table) to calculate the pH. a solution that is 0.205 M in CH3NH2 and 0.110 M in CH3NH3Br. i used th Ka of CH3NH2 and set up the problem as Ka=[H3O][CH3NH2]/[CH3NH3Br], but that was wrong.

3. ### Science

1. Which of the following best explains what an Engineer does? A- An engineer combines the knowledge with problem-solving skills to design better mathematical models. B-An engineer combines the knowledge with problem-solving

4. ### algebra

Explain the difference between solving a system of equations by the algebraic method and the graphical method. Someone also wants to know why there are different methods for solving the same problem-what would you tell him?

1. ### Career planning

Which of the following is an effective first reaction to a problem . A. Asking questions to help you understand the problem B. Deciding on a solution as quickly as possiable C. Finding someone else to handle the problem D.

2. ### Chemistry

An alpha particle (mass 6.6 x 10^-24 grams) emitted by radium travels at 3.4 x 10^7 plus or minus 0.1 x 10^7 mi/h. (a) What is its de Broglie wavelength (in meters)? (b) Whats uncertainty in its position? for part (a) I got 1.53

3. ### Calculus - average velocity

*VELOCITY OF A CAR* Suppose the distance s (in feet) covered by a car moving along a straight road after t sec is given by the function s = f(t) = 2t^2 + 48t. a. Calculate the average velocity of the car over the time intervals

4. ### math prob:(

a. Solve a – 9 = 20 b. Solve b – 9 > 20 c. How is solving the equation in part a similar to solving the inequality in part b? d. How are the solutions different?

1. ### statistics

in a classic study of problem solving, katona demonstrated that people whoa re required to figure out a problem on their own will learn more than people who are given the solution. One group of participants is presented with a

2. ### math

Consider the pair of linear equations below. 4x+6y=12 2x+3y=6 Part A: What is the relationship, if any, between 12 and 6? Part B: Do the two equations have one solution, no solution, or infinitely many solution? Explain. Part C:

3. ### Calculus (pleas help!!!)

A) If x^2+y^3−xy^2=5, find dy/dx in terms of x and y. dy/dx=________ B) Using your answer for dy/dx, fill in the following table of approximate y-values of points on the curve near x=1 y=2. 0.96 ______ 0.98 ______ 1.02 ______

4. ### Math

a.) Solve a - 9 = 20 b.) Solve b - 9 > 20 c) How is solving the equation in part a similar to solving the inequality in part b? d.) How are the solutions different?