Question

need help on the attachment

Answer 1

come on no has helped you with this yet?

Answer 2

no

Answer 3

should i solve this or go to sleep.....

Answer 4

solve before going, please

Answer 5

Oops! forgot to sleep after going

Answer 6

okay, first things first, lets find the first derivaitve of the function your where given

Answer 7

can you find it?

Answer 8

9sec^(2)x

Answer 9

okay good

Answer 10

now can you please evaluate:
f(pi/4)=9sec^2(pi/4)

Answer 11

square root of 2

Answer 12

is it right?

Answer 13

basically to make it more accesible we can write this as:
f(pi/4)=9[sec(pi/4)]^2

Answer 14

further more we can write it as: f(pi/4)=9[1/cos(pi/4)]^2

Answer 15

then evalutaing we get:

f(pi/4)=9[1/sqrt(2)/(2)]^2

Answer 16

what square root 2/2???

Answer 17

further: f(pi/4)=9[sqrt(2)]^2

which the gives us: f(pi/4)=9(2), which is 18

Thus f(pi/4)=18

Answer 18

yes, look at the unit circle, at pi/4 or 45 degrees, cos is sqr(2)/2, now if we rationalize the numerator we get just sqrt(2)

Answer 19

oh, thought your doing sec

Answer 20

i rewrote secx as 1/cosx

Answer 21

how come?

Answer 22

just to make is easier for me, but if realise that sec(pi/4) is sqrt(2) then more power to you

Answer 23

Now we have found the slope (m) of our line, it is 18

Answer 24

y-y=m(x-x)

Answer 25

yes, but we will use this form, y=mx+b

Answer 26

i am getting sleepy lets finish this problem

Answer 27

ok

Answer 28

what would be the b in the slope formula

Answer 29

Now remeber we said, that we have the x coordinate in the beining of pi/4, lets evaluate the orginal function at this point, this will give us the y in our line.

f(pi/4)=9tan(pi/4)
=9(1)
=9

now we have our x which is pi/4, we have our slope which is 18, lets plug this info into our line:

9=18(pi/4)+b

this means that b is = to 9-18pi/4

Answer 30

now lets substitute everyting in:

y=18x-(36-18pi)/(4)

Answer 31

are we good?

Answer 32

36??

Answer 33

i combined 9 and 18pi/4

Answer 34

yes?

Answer 35

still don't see how you can 36??