Question

Help please!! :)

Answer 1

The length of a day in Philadelphia, Pennsylvania, is given by the sinusoidal function, f(t), which represents the number of hours of daylight t days into the year: f(t) = 11 + 2.2sin((2π/365)t - 1.25) . How many hours of daylight are there on the tenth day of the year? Round the answer to the nearest tenth.

Answer 2

Can you please help me understand this ?

Answer 3

I tried looking it up but found no help :/

Answer 4

Yeah i think you plug 10 into t but i dont know how to put it in my calculator

Answer 5

hmmm..... can u say from which part u need help...
do u need help in finding the answer ?

Answer 6

yea

Answer 7

so...
the equation is like this..
f(t) = 11 + 2.2sin((2π/365)t - 1.25)
and u need to find the no. hour of daylight on the 10th day....
which mean u need to find the value of f(x) when t is 10
basically u need to find f(10)


now u can c that the term t is repeated only once in the equation
sin((2π/365)t - 1.25)
u have to plug 10 here where u will get
sin((2π/365)10 - 1.25)
now it's
sin((20π/365) - 1.25)
now u need to find the value of
sin((20π/365) - 1.25)
and
solve the equation
11 + 2.2sin((20π/365) - 1.25)

did u get it ?

Answer 8

Okay so i'd do sin(20π/365) - 1.25 in my calculator?

Answer 9

i got -.01881

Answer 10

i put the whole equation in my calculator and got 10.9

Answer 11

or 11

Answer 12

nope ... u have to find the sin value of this whole expression u get when u simplify
sin [ (20π/365) - 1.25 ]
it's not
sin(20π/365) - 1.25 :)

Answer 13

So.. what do i do first? [ (20π/365) - 1.25 ] this?

Answer 14

or do i convert 20π/365 to degrees?

Answer 15

yep

Answer 16

okay so 20π/365 = 180/π?

Answer 17

is it 9.8

Answer 18

no... i said yep to
So.. what do i do first? [ (20π/365) - 1.25 ] this? .
srry... my comment has posted after sometime i typed it

Answer 19

Oh sorry im so confused haah.

Answer 20

how do i solve that? i forgot

Answer 21

first find the value u get when u simplify
(20π/365)
and subtract
1.25 from it
then
find the sin value of your answer

Answer 22

so .1721 - 1.25 =

Answer 23

-1

Answer 24

yeah...!

Answer 25

so now 11 + 2.2sin(-1) ?

Answer 26

is it 10.96 or 11

Answer 27

yes... go on

Answer 28

Thats what i got for my answe

Answer 29

10.96

Answer 30

yes...!! that's the answer for ur question :)

Answer 31

Thank you so much! You were a big help :)

Answer 32

u r welcome...!! :)