Answer: C. 1998, 2000, 2002
Answer:
9x+3
Step-by-step explanation:
First join the x terms, and you will find 9x (1x+8x), then join the numbers, and you get 3 (-7+10)
Hope it helps!
Answer:
whats the answer?
Step-by-step explanation:
7, 5, 3, 1 is an arithmetic sequence with common difference (d) = -2 and first term (a) = 7.
Tn = a + (n -1)d
T50 = 7 + (50 - 1) x -2 = 7 + 49 x -2 = 7 - 98 = -91
50th term = -91
sinA - cosA +1 / sinA + cosA -1 = secA + tanA
Now secA = 1/cosA and tanA = sinA/cosA
So sinA - cosA +1 / sinA + cosA -1 = 1/cosA + sinA / cosA
From now on I'll write sinA = s and cosA = c :-
(s - c + 1 )/ (s + c - 1) = 1/c + s/c
(s - c + 1) / (s + c - 1) = (1 + s) / c
Cross multiply:-
s + c - 1 + s^2 + sc - s = sc - c^2 + c
s^2 + c + sc - 1 = sc - c^2 + c
s^2 - 1 + sc - sc + c - c = -c^2
s^2 - 1 = -c^2
-(1 - s^2) = - c^2
Now 1 - s^2 = c^2 so:-
- c^2 = - c^2
So the identity is proved
