# Maths and science

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The sum of the first n terms of a sequence is given by 4-4(1/2)^n.calculate the first 3 terms

• Maths and science -

term(1) = 4 - 4(1/2)^1 = 4 - 2 = 2
term(2) = 4 - 4(1/2)^2= 4-4(1/4) = 3
term(3) = 4-4(1/2)^3
= 4 - 4(1/8)
= 4 - 4/8
= 4 - 1/2 = 3 1/2 or 7/2 or 3.5

so to get any term, e.g. term(5), replace n with the term number you want, in this case n=5

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