What is the answer to this equation?
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Answer:a4=-42
Step-by-step explanation:
a1=0
an=2(a(n-1)-3)
a4=2(a(4-1)-3)
a4=2(a3-3)
a3=2(a(3-1)-3)
a3=2(a2-3)
a2=2(a(2-1)-3)
a2=2(a1-3) but a1=0
a2=2(0-3)
a2=2(-3)
a2=-6
a3=2(a2-3)
a3=2(-6-3)
a3=2(-9)
a3=-18
a4=2(a3-3)
a4=2(-18-3)
a4=2(-21)
a4=-42