Think of the SS numbers as being a collection of digits. If any of the digits (say the first one for example) are 8 then all the remaining digits can be anything but 8, meaning there are 9 choices for each remaining digit. This effectively becomes an 8 digit number with the constraint that there can only be 9 choices for a digit. This means for the first digit being 8 we have 9⁸ remaining possible numbers. Since we will do this for each of the remaining digits (they each get to be 8 then we count their 9⁸ configurations) we end up with 9(9⁸) or 9⁹≈3.8742E8
9514 1404 393
Answer:
more than 9 hours
Step-by-step explanation:
Goran's net earnings for h hours work will be ...
7h -5 . . . . hourly pay less equipment fees
He wants this amount to be more than $58:
7h --5 > 58
7h > 63 . . . . . add 5
h > 9 . . . . . . divide by 7
Goran could trim trees for more than 9 hours.
Answer:
-7845
Step-by-step explanation:
17-(8 to the power of 3-45) times 7 times 2 -1324=-7845
Tan⁴x - sec⁴x = 1 - 2sec²x
tan²x = sec²x - 1
tan⁴x - sec⁴x = 1 - 2sec²x
(tan²x)² - sec⁴x = 1 - 2sec²x
(sec²x - 1)² - sec⁴x = 1 - 2sec²x
(sec²x)² - 2 * sec²x + 1 - sec⁴x = 1 - 2sec²x
sec⁴x - 2 sec²x + 1 - sec⁴x = 1 - 2sec²x
sec⁴x can be cancelled:
- 2 sec²x + 1 = 1 - 2sec²x
1 - 2sec²x = 1 - 2sec²x
