Cosine is the adjacent side over the hypotenuse (You can remember sin, cos, and tan by using sohcahtoa or sin = opposite/hypotenuse, cos = adjacent/hypotenuse, tan = opposite over adjacent). I think a picture would help, too.

I attached a picture of what I think the triangle would look like.

If the picture is right (we're assuming it is) and going with what we're given (the triangle was addressed as triangle XYZ, meaning that <u>angle Y is in the middle and that's the one we'll use</u>).

Looking at my picture then:

$cos=\frac{64}{80} \\cos=\frac{8}{10} \\cos=\frac{4}{5}$ .

6 0

3 years ago

Th term of a seq uence is n(n-4) /n+3 Work out the sum of the 1st and 6th terms.

AlekseyPX

Answer:

7/12

Step-by-step explanation:

The nth term Tₙ = n(n-4) /n+3.

The 1st term T₁ = 1(1 - 4)/(1 + 3) = -3/4

The 6th term T₆ = 6(6 - 4)/(6 + 3) = 6(2)/9 = 2(2)/3 = 4/3

So, the sum of the 1st and 6th terms is T₁ + T₆ = -3/4 + 4/3

= (-9 + 16)/12

= 7/12

5 0

3 years ago