#3**+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.

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

Cosine(theta)=sine(90-theta)

**Co**tangent stands for complementary ratio of tan

Cot(theta)=tan(90-theta)

**Co**sec stands for complementary ratio of sec

cosec(theta)=sec(90-theta)

If you remember this it can help a lot.

Melody
Sep 14, 2014

#2**+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**+10 **

Best Answer

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.

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

Cosine(theta)=sine(90-theta)

**Co**tangent stands for complementary ratio of tan

Cot(theta)=tan(90-theta)

**Co**sec stands for complementary ratio of sec

cosec(theta)=sec(90-theta)

If you remember this it can help a lot.

Melody
Sep 14, 2014

#6**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