The formula is [tex]\frac{a_1(1-r^n)}{1-r}[/tex] a1=first term n=which term r=common ratio we see the common ratio is -2 frs term is 1 and we go to 10th term so n=10
[tex]\frac{1(1-(-2)^{10})}{1-(-2)}[/tex] [tex]\frac{1(1-1024)}{1+2}[/tex] [tex]\frac{1(-1023)}{3}[/tex] -341 the sum is -341
It's b. -1,-2,-4,-8,-16,-32 because [tex]a_n=2a_{n-1} \mbox{ where } a_1=-1.\\ So\\ a_2=2a_1=-2\\ a_3=2a_2=-4\\ a_4=2a_3=-8\\ a_5=2a_4=-16\\ a_6=2a_5=-32.[/tex]
The formula is
[tex]\frac{a_1(1-r^n)}{1-r}[/tex]
a1=first term
n=which term
r=common ratio
we see the common ratio is -2
frs term is 1
and we go to 10th term so n=10
[tex]\frac{1(1-(-2)^{10})}{1-(-2)}[/tex]
[tex]\frac{1(1-1024)}{1+2}[/tex]
[tex]\frac{1(-1023)}{3}[/tex]
-341
the sum is -341
The next will be 64, -128 each on is * by 2 and switching from pos to neg
-4/2
Step-by-step explanation:
just take 4 and divide it by -2 and youll get the common ratio as-2
Hope it helps
The answer to this is B. " -1 , -2 , -4, - 8, -16 , -32
It's b. -1,-2,-4,-8,-16,-32
because
[tex]a_n=2a_{n-1} \mbox{ where } a_1=-1.\\ So\\ a_2=2a_1=-2\\ a_3=2a_2=-4\\ a_4=2a_3=-8\\ a_5=2a_4=-16\\ a_6=2a_5=-32.[/tex]
you multiply it by -2 each time
Explanation:
positive times negative = negative
negative times negative= positive
- 32 x -2 = 64
64 x -2 = -128
Step-by-step explanation:
Each item is multiplied by -2
the answer is,
-2, 4, -8, 16, -32, 64
Remark
You can find the answer to that by dividing any 2 consecutive terms putting the right one in the numerator and the left one in the denominator.
Forumula
ratio = right/left
right = - 8
left = 4
ratio = -8/4
ratio = -2
Any two numbers would work.
ratio = - 32/16 = - 2
Hello,
[tex]u_{1}= -2 \\ u_{2}= -2 *(-2)=(-2)^2 \\ u_{3}= (-2)^2 *(-2)=(-2)^3 \\ u_{4}= (-2)^3 *(-2)=(-2)^4 \\ ...\\ \boxed{u_{n}= (-2)^n} \\ [/tex]