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Find the 1111 values of xx.\newlinelog2(x+2)+log2(x+6)=5\log_{2}(x+2)+\log_{2}(x+6)=5

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Q. Find the 1111 values of xx.\newlinelog2(x+2)+log2(x+6)=5\log_{2}(x+2)+\log_{2}(x+6)=5
  1. Combine logarithmic expressions: Apply the product rule of logarithms to combine the two logarithmic expressions.\newlineThe product rule of logarithms states that logb(a)+logb(c)=logb(ac)\log_b(a) + \log_b(c) = \log_b(a*c), where bb is the base of the logarithms.\newlinelog2(x+2)+log2(x+6)=log2((x+2)(x+6))\log_2(x+2) + \log_2(x+6) = \log_2((x+2)(x+6))
  2. Set equal and rewrite: Set the combined logarithm equal to 55 and rewrite the equation in exponential form.log2((x+2)(x+6))=5\log_2((x+2)(x+6)) = 5 can be rewritten as 25=(x+2)(x+6)2^5 = (x+2)(x+6)
  3. Calculate and expand: Calculate 252^5 and expand the right side of the equation.\newline25=322^5 = 32\newline(x+2)(x+6)=x2+6x+2x+12(x+2)(x+6) = x^2 + 6x + 2x + 12\newlinex2+8x+12=32x^2 + 8x + 12 = 32
  4. Subtract and solve for x: Subtract 3232 from both sides of the equation to set it to zero and solve for xx.\newlinex2+8x+1232=0x^2 + 8x + 12 - 32 = 0\newlinex2+8x20=0x^2 + 8x - 20 = 0
  5. Factor the quadratic: Factor the quadratic equation.\newlineWe need to find two numbers that multiply to 20-20 and add up to 88. These numbers are 1010 and 2-2.\newline(x+10)(x2)=0(x + 10)(x - 2) = 0
  6. Solve for x: Solve for x by setting each factor equal to zero.\newlinex+10=0x + 10 = 0 or x2=0x - 2 = 0\newlinex=10x = -10 or x=2x = 2
  7. Check for extraneous solutions: Check for extraneous solutions by substituting the values of xx back into the original logarithmic equation.\newlineFor x=10x = -10:\newlinelog2(10+2)+log2(10+6)\log_2(-10+2) + \log_2(-10+6) is undefined because logarithms of negative numbers are not real.\newlineFor x=2x = 2:\newlinelog2(2+2)+log2(2+6)=log2(4)+log2(8)=2+3=5\log_2(2+2) + \log_2(2+6) = \log_2(4) + \log_2(8) = 2 + 3 = 5, which is true.

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