What is the value of the 11th term in the sequence -3, -6, -12, -24

You would use any explicit rule to find this:
f(n)= f(1)+(n-1)d 
     
      f(1) is the first term of the sequence
      r  is the common difference

f(n)= -3+(n-1)×2
f(11)= -3+(11-1)×2         n=11 since you want the 11th term
f(11)= -3+(10)×2
f(11)= -3+20
f(11)= 17

the 11th term of the sequence is 17

In this sequence we get the next number by multiplying the previous number by 2
-3 , -6 , -12, -24, -48, -96, -192, -384, -768, -1536, -3072
the value of the 11th term in the sequence is -3072 

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