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5) Solve the simultaneous equations log(x+y)=0 Solve the simultaneous equations 2logx=log(y+1)​

User ToDayIsNow
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1 Answer

12 votes

Answer:

(1,0)

Explanation:

Since log (x+y) = 0 you should know x+y = 1

so y = (1-x)

then 2 logx = log (y+1)

log x^2 = log (1-x +1) = log (2-x)

x^2 = 2-x

x^2 + x-2 = 0

(x+2)(x-1) = 0 so x = -2 or +1

then y = 3 or 0

-2,3 and 1,0 since you cannot have a log of a negative number

the only answer is (1,0)

User David Sacks
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