Answer:
-90 , 30
Step-by-step explanation:
sina = cos(2a)
= 1 - 2(sina)^2
2(sina)^2 + sina -- 1 = 0
( sina + 1 )( 2sina - 1 ) = 0
sina = -1 or sina = 1/2
=> a = -90 degrees or => a = 30 degrees
17^2 = 289
18^2 = 324
Any of the numbers between 289 and 324 exclusive will have a root between 17 and 18
Eg sr(300) = 17.3205... is between 17 and 18 on the number line.
There are 33 other whole number answers you could pick
Answer:
i think its a but im not sure if those are the only two options
Step-by-step explanation: