Question:hard

If \(x = (4096)^{7+4√3}\), then which of the following equals \(64\) ?

Updated On: Jan 15, 2026
  • \(\frac{x^7}{x^{2\sqrt3}}\)
  • \(\frac{x^7}{x^{4\sqrt3}}\)
  • \(\frac{x\frac{7}{2}}{x^{\frac{4}{\sqrt3}}}\)
  • \(\frac{x\frac{7}{2}}{x^{2\sqrt3}}\)
Show Solution

The Correct Option is D

Solution and Explanation

Let \( x = (4096)^{7 + 4\sqrt{3}} \).

Given that \( 4096 = 2^{12} \), we can write:

\[ x = (2^{12})^{7 + 4\sqrt{3}} = 2^{12(7 + 4\sqrt{3})} = 2^{84 + 48\sqrt{3}} \]

We will now evaluate each option to determine which expression equals \( 64 = 2^6 \).

Option 1: \( \frac{x^7}{x^{2\sqrt{3}}} = x^{7 - 2\sqrt{3}} \)

\[ x^{7 - 2\sqrt{3}} = \left(2^{84 + 48\sqrt{3}}\right)^{7 - 2\sqrt{3}} = 2^{(84 + 48\sqrt{3})(7 - 2\sqrt{3})} \]

Expanding the exponent: \[ 84 \cdot 7 + 84 \cdot (-2\sqrt{3}) + 48\sqrt{3} \cdot 7 + 48\sqrt{3} \cdot (-2\sqrt{3}) \] \[ = 588 - 168\sqrt{3} + 336\sqrt{3} - 288 = 300 + 168\sqrt{3} \]

Therefore, the result is: \[ 2^{300 + 168\sqrt{3}} eq 64 \]

Option 2: \( \frac{x^7}{x^{4\sqrt{3}}} = x^{7 - 4\sqrt{3}} \)

\[ x^{7 - 4\sqrt{3}} = \left(2^{84 + 48\sqrt{3}}\right)^{7 - 4\sqrt{3}} = 2^{(84 + 48\sqrt{3})(7 - 4\sqrt{3})} \]

Expanding the exponent: \[ 84 \cdot 7 + 84 \cdot (-4\sqrt{3}) + 48\sqrt{3} \cdot 7 + 48\sqrt{3} \cdot (-4\sqrt{3}) \] \[ = 588 - 336\sqrt{3} + 336\sqrt{3} - 576 = 12 \]

Thus, the result is: \[ 2^{12} = 4096 eq 64 \]

Option 3: \( \frac{x^{7/2}}{x^{4/\sqrt{3}}} = x^{\frac{7}{2} - \frac{4}{\sqrt{3}}} \)

\[ x^{\frac{7}{2} - \frac{4}{\sqrt{3}}} = \left(2^{84 + 48\sqrt{3}}\right)^{\frac{7}{2} - \frac{4}{\sqrt{3}}} \]

This expression does not simplify to a neat integer power of 2. Therefore, it is also incorrect.


Option 4: \( \frac{x^{7/2}}{x^{2\sqrt{3}}} = x^{\frac{7}{2} - 2\sqrt{3}} \)

\[ x^{\frac{7}{2} - 2\sqrt{3}} = \left(2^{84 + 48\sqrt{3}}\right)^{\frac{7}{2} - 2\sqrt{3}} = 2^{(84 + 48\sqrt{3})(\frac{7}{2} - 2\sqrt{3})} \]

Expanding the exponent: \[ 84 \cdot \frac{7}{2} + 84 \cdot (-2\sqrt{3}) + 48\sqrt{3} \cdot \frac{7}{2} + 48\sqrt{3} \cdot (-2\sqrt{3}) \] \[ = 294 - 168\sqrt{3} + 168\sqrt{3} - 288 = 6 \]

Consequently, the result is: \[ 2^6 = 64 \]


Final Answer: \( \boxed{\frac{x^{7/2}}{x^{2\sqrt{3}}}} \)

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