The 20th term of the sequence that begins as -4,8,-16,32,...is 2097152.
What is a geometric progression?
It is a type of sequence in which all the elements have common ratio. To calculate the common ratio we apply the following formula:
Ratio=a n/ a n-1
How to solve a geometric progression?
If we carefully watch our sequence we will be able to find that it is a geometric progression because all the terms have common ratio of -2.
To calculate the 20th term we will apply the formula:
20th term =[tex]ar^{20-1}[/tex]
=-4* [tex](-2)^{19}[/tex]
=-4*-524288
=2097152
Hence the 20 th term is 2097152.
Learn more about geometric progression at https://brainly.com/question/12006112
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