Solve for x : log (x^2 − 21) = 2

Given, ⇒ log (x2 − 21) = 2 ⇒ log (x2 − 21) = 2 log 10 ⇒ log (x2 − 21) = log 100 ⇒ (x2 − 21) = 100 ⇒ x2 = 100 + 21 ⇒ x2 = 121 ⇒ x = ⇒ x = 11. Hence, the value of x = 11.

Mathematics

Solve for x :
log (x² − 21) = 2

Logarithms

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Answer

Given,

⇒ log (x² − 21) = 2

⇒ log (x² − 21) = 2 log 10

⇒ log (x² − 21) = log 100

⇒ (x² − 21) = 100

⇒ x² = 100 + 21

⇒ x² = 121

⇒ x = $\sqrt{121}$

⇒ x = ±11.

Hence, the value of x = ±11.

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Mathematics

Solve for x :
log (x² − 21) = 2

Logarithms

Answer

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Mathematics

Solve for x :log (x2 − 21) = 2

Logarithms

Answer

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Solve for x :
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