+0

cos12-sin78

0
1614
9

cos12-sin78

Guest Sep 14, 2014

#3
+94114
+10

It was cluey for you to notice that Chris.

Complementary angles are angles that add up to 90.

Complementary trig ratios are ones where the values are equal for complementary angles.

I am probably not wording that very well.

Cosine stands for complementary ratio of sine   (at least that is how I think of it)

Cosine(theta)=sine(90-theta)

Cotangent stands for complementary ratio of tan

Cot(theta)=tan(90-theta)

Cosec stands for complementary ratio of sec

cosec(theta)=sec(90-theta)

If you remember this it can help a lot.

Melody  Sep 14, 2014
#1
+27229
+5

Alan  Sep 14, 2014
#2
+92763
+10

We don't really need to use any calculators here.......

Notice that cosA = sin(90 - A)

So

cos 12  = sin(90 - 12)

cos12  =  sin 78

And, if like things are subtracted, the answer  = 0 !!!!

CPhill  Sep 14, 2014
#3
+94114
+10

It was cluey for you to notice that Chris.

Complementary angles are angles that add up to 90.

Complementary trig ratios are ones where the values are equal for complementary angles.

I am probably not wording that very well.

Cosine stands for complementary ratio of sine   (at least that is how I think of it)

Cosine(theta)=sine(90-theta)

Cotangent stands for complementary ratio of tan

Cot(theta)=tan(90-theta)

Cosec stands for complementary ratio of sec

cosec(theta)=sec(90-theta)

If you remember this it can help a lot.

Melody  Sep 14, 2014
#4
+92763
0

Well....I DO have my "moments".......(every now and then) (LOL!!!)

CPhill  Sep 14, 2014
#5
+94114
0

Yes you have your clever moments very often.

Melody  Sep 14, 2014
#6
+92763
0

Yeah...even if Alan and I disagree about how long it takes for 62 apples to fall off a tree.....I was assuming that the first apple was "on the fence" about the whole thing and it took him/her almost 3 hrs. to decide to take the "plunge"  ...........either way, it's either 7.2 days or 7.3 days.......depending upon your local time zone and prevailing gravitational conditions, of course.......!!!

CPhill  Sep 14, 2014
#7
+94114
0

Yea apples are fickled things - they fall with the wind.     LOL

Melody  Sep 14, 2014
#8
+27229
0

Well spotted Chris!

Alan  Sep 14, 2014
#9
+94114
0

Alan, do you like classical music?

I'm enjoying this.