Problem

log2(x+6)+log2(x+5)=1

Answer

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Answer

Therefore, the original equation log2(x+6)+log2(x+5)=1 has no solution.

Steps

Step 1 :log2(x+6)+log2(x+5)=1 becomes log2[(x+6)(x+5)]=1 using the property of logarithms logb(m)+logb(n)=logb(mn).

Step 2 :log2[(x+6)(x+5)]=1 becomes 21=(x+6)(x+5) by converting the logarithmic equation to an exponential equation.

Step 3 :2=(x+6)(x+5) simplifies to 2=x2+11x+30.

Step 4 :2=x2+11x+30 rearranges to x2+11x+302=0, which simplifies to x2+11x+28=0.

Step 5 :x2+11x+28=0 factors to (x+4)(x+7)=0.

Step 6 :Setting each factor equal to zero gives x=4 and x=7.

Step 7 :Checking the solutions in the original equation, we find that both x=4 and x=7 are undefined in the original equation because the domain of the logarithm function is (0,).

Step 8 :Therefore, the original equation log2(x+6)+log2(x+5)=1 has no solution.

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