Expert: Paul Klarreich - 5/9/2008

Question
GOOD DAY!
I'm having trouble answering these questions ,can you  check it for me...the more i try the more getting far with the right answer ..Thanks a lot! kindly answer this with solutions for me to understand where i mess it up.


Find the acute angle A to the nearest second when:

a.sin A = 0.30985
b.cot A=0.52613
c.cos A=0.77273
d.tan A=6.63831
e.sin A=0.10655
f.cos A=0.55570
g.sin A=0.92112
h.tan A=0.13476
i.cot A=0.32323
j.cos A=0.75273


Answer  
a.)
sin(A) = 0.30985
A = sin^-1(.30985)
A = 18°3'0.69"

-----------------

b.)
cot(A) = 0.52613
tan(A) = 1/(.52613)
A = tan^-1(1/.52613)
A = 62°14'59.27"

------------------------

c.)
cos(A) = 0.77273
A = cos^-1(.77273)
A = 39°24'1.16"

--------------------------

d.)
tan(A) = 6.63831
A = tan^-1(6.63831)
A = 81°26'00

--------------------------

e.)
sin(A) = 0.10655
A = sin^-1(.10655)
A = 6°6'59.31

--------------------------

i.)
cot(A) = 0.32323
tan(A) = 1/(.32323)
A = tan^-1(1/.32323)
A = 72°5'15.4"
   those letters that i did not type my answers,that what i mess  up the most.

find the following functions correct to five decimal places:



a.sin 22°43'
answer 0.38617

b.cos 44°56'
answer 0.70793

c.sin 49°17'
answer 0.64657

d.tan 11°37'
answer  0.20557


e.sin 79°23'30"
answer 0.18456

f.cot 19°0'25"
 answer  0.56892

g.tan 64°6'45"
answer  0.15689

h.cos 29°45'48"
 answer  0.12896

i.cot 78°45'50"
 answer 0.58462

j.cos 15°12'51"
 answer 0.15869

once again thank you very much!

Answer
Questioner:   grace
Category:  Advanced Math
Private:  No
 
Subject:  plane trigonometry
Question:  GOOD DAY!
I'm having trouble answering these questions ,can you  check it for me...the more i try the more getting far with the right answer ..Thanks a lot! kindly answer this with solutions for me to understand where i mess it up.


Find the acute angle A to the nearest second when:

a.sin A = 0.30985
b.cot A=0.52613
c.cos A=0.77273
d.tan A=6.63831
e.sin A=0.10655
f.cos A=0.55570
g.sin A=0.92112
h.tan A=0.13476
i.cot A=0.32323
j.cos A=0.75273


Answer  
a.)
sin(A) = 0.30985
A = sin^-1(.30985)
A = 18°3'0.69"

>> I suggest this routine: Again, Excel is good for this:

Cell 1: 0.30985
Cell 2: =ASIN(cell 1)*180/PI()
Cell 3: =INT(C2)  <<    THAT'S YOUR DEGREES.
Cell 4: =(c2 - c3)*60
Cell 5: =INT(C4)   << THAT'S YOUR MINUTES.
Cell 6: =INT((C4 - C5) * 60)  << THAT'S YOUR SECONDS.


-----------------

b.)
cot(A) = 0.52613
tan(A) = 1/(.52613)
A = tan^-1(1/.52613)
A = 62°14'59.27"

------------------------

c.)
cos(A) = 0.77273
A = cos^-1(.77273)
A = 39°24'1.16"

--------------------------

d.)
tan(A) = 6.63831
A = tan^-1(6.63831)
A = 81°26'00

--------------------------

e.)
sin(A) = 0.10655
A = sin^-1(.10655)
A = 6°6'59.31

--------------------------

i.)
cot(A) = 0.32323
tan(A) = 1/(.32323)
A = tan^-1(1/.32323)
A = 72°5'15.4"
those letters that i did not type my answers,that what i mess  up the most.

find the following functions correct to five decimal places:

=============== THESE ARE THE SAME AS THE LAST ANSWER ========

a.sin 22°43'
answer 0.38617

b.cos 44°56'
answer 0.70793

c.sin 49°17'
answer 0.64657

d.tan 11°37'
answer  0.20557


e.sin 79°23'30"
answer 0.18456

f.cot 19°0'25"
answer  0.56892

g.tan 64°6'45"
answer  0.15689

h.cos 29°45'48"
answer  0.12896

i.cot 78°45'50"
answer 0.58462

j.cos 15°12'51"
answer 0.15869

once again thank you very much!
....................................
Hi again, Grace,

You did not indicate what you did to get your answers, so I can't check your mathematics (let alone your arithmetic). And this is not an 'arithmetic-checking' site.  That's why you have answers in the back of the book.

Send me a problem (not ten) you are having trouble with, tell me what you did, and then I'll try to help.