Math

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Find the sum of the G.p.2+6+18+54+...+1458

• Math -

a = 2
r = 3
2*729 = 1458
729 = 3^6, so

S7 = 2(3^7-1)/(3-1) = 2*2186/2 = 2186

• Math -

Solve the equation simultaneously.1/3x+y=3,x+1/2y=4

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