Let's work on the left side first. And remember that
the<u> tangent</u> is the same as <u>sin/cos</u>.
sin(a) cos(a) tan(a)
Substitute for the tangent:
[ sin(a) cos(a) ] [ sin(a)/cos(a) ]
Cancel the cos(a) from the top and bottom, and you're left with
[ sin(a) ] . . . . . [ sin(a) ] which is [ <u>sin²(a)</u> ] That's the <u>left side</u>.
Now, work on the right side:
[ 1 - cos(a) ] [ 1 + cos(a) ]
Multiply that all out, using FOIL:
[ 1 + cos(a) - cos(a) - cos²(a) ]
= [ <u>1 - cos²(a)</u> ] That's the <u>right side</u>.
Do you remember that for any angle, sin²(b) + cos²(b) = 1 ?
Subtract cos²(b) from each side, and you have sin²(b) = 1 - cos²(b) for any angle.
So, on the <u>right side</u>, you could write [ <u>sin²(a)</u> ] .
Now look back about 9 lines, and compare that to the result we got for the <u>left side</u> .
They look quite similar. In fact, they're identical. And so the identity is proven.
Whew !
Answer:
The midpoint of TS is (-1,-3)
The coordinates of M should be (8,18)
Step-by-step explanation:
Answer:
For a circle.
Step-by-step explanation:
A=πr^2
7. 20
8. 680
9. 700
10. 4,000
11. 106,000
12. 5,800
Answer:
an = 12 -7(n-1)
an = 19-7n
Step-by-step explanation:
The explicit formula for an arithmetic sequence is
an = a1 +d(n-1) where a1 is the first term and d is the common difference
a1 =12
We find d by taking the second term and subtracting the first term
d = 5-12
d = -7
an = 12 -7(n-1)
We can simplify this
an = 12 -7n+7
an = 19-7n
