6 - 34 + 96 - 384 +...
a 1 = 6 , a 2 = a 1 * ( - 4 ) , a 3 = a 2 * ( - 4 ), a 4 = a 3 * ( - 4)...
a 5 = - 384 * ( - 4 ) = 1,536
a 6 = 1536 * ( - 4 ) = - 6,144
a 7 = - 6,144 * ( - 4 ) = 24,576
This is a sum of a geometric sequence:
S 7 = 6 - 24 + 96 - 384 + 1,536 - 6,144 + 24,576 = 19,662
Another way to solve this:
S 7 = a 1 * ( r^n - 1) / ( r - 1 ) = 6 * (( - 4) ^7 - 1 )/ (- 4 - 1)=
= 6 * (-16,385) / (-5 ) = 19,662
Answer:
I think D
Step-by-step explanation:
Are you asking to simplify all of those equations?
You can just multiply the top and the bottom by 2, to get the bottom to be 10. So you get -164/10. From here you can see that 10 goes into 164,16.4 times.
Therefore, -82/5 = -16.4
Answer:
Im not entirely sure this is right but
0 = tan^-1(20 ÷ 25)
0 ≈ 38.65°
hope i helped lol