In an A.P a=2, d=30, sn=800 find n=?
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Answer:
explain the term zygote
Step-by-step explanation:
explain the term zygote
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Step-by-step explanation:
a=2,d=8,sn=90
sn=2n[2a+(n−1)d]90=2n[4+(n−1)8]
180=n[8n−4]
180=8n2−4n
=8n2−4n−180=0
=2n2−n−45=0
=2n2−10n+9n−45=0
=2n(n−5)−9(n−5)
=(2n−9)(n−5)
n=5
an=a+(n−1)dan=2+(5−1)8an=2+32an=34
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