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Zorluk: OrtaOperations with Variable Exponents

A student is asked to simplify the rational algebraic expression shown below.

(3a2b−3)23a−1b−4 \frac{(3a^2b^{-3})^2}{3a^{-1}b^{-4}}

What is the fully simplified form of this expression with positive exponents?

  1. 3a5b2\frac{3a^5}{b^2}Cevap
  2. B
    a5b2\frac{a^5}{b^2}
  3. C
    3a3b10\frac{3a^3}{b^{10}}
  4. D
    a6b2a^6b^2

Cevap

3a5b2\frac{3a^5}{b^2}
To simplify the expression, first simplify the numerator by squaring every factor inside the parentheses: (3)2⋅(a2)2⋅(b−3)2(3)^2 \cdot (a^2)^2 \cdot (b^{-3})^2, which yields 9a4b−69a^4b^{-6}. Next, divide this result by the denominator 3a−1b−43a^{-1}b^{-4}. Divide the coefficients: 9÷3=39 \div 3 = 3. Then, apply the quotient rule by subtracting the exponents of like bases: for aa, 4−(−1)=54 - (-1) = 5; for bb, −6−(−4)=−2-6 - (-4) = -2. This gives 3a5b−23a^5b^{-2}. Finally, rewrite the expression with positive exponents by moving b−2b^{-2} to the denominator, resulting in 3a5b2\frac{3a^5}{b^2}.

Adım Adım Çözüm

1
Apply the power of a product and power of a power rules to the numerator: (3a2b−3)2(3a^2b^{-3})^2.
9a4b−69a^4b^{-6}
The exponent outside the parentheses applies to the coefficient and is multiplied by each variable's exponent.
2
Substitute the expanded numerator back into the fraction.
9a4b−63a−1b−4\frac{9a^4b^{-6}}{3a^{-1}b^{-4}}
This sets up the expression for the quotient rule.
3
Divide the numerical coefficients.
9÷3=39 \div 3 = 3
Coefficients are divided normally.
4
Apply the quotient rule by subtracting the denominator's exponents from the numerator's exponents for bases aa and bb.
a4−(−1)=a5a^{4 - (-1)} = a^5 and b−6−(−4)=b−2b^{-6 - (-4)} = b^{-2}
When dividing like bases, exponents are subtracted. Care must be taken with double negative signs.
5
Combine the results and convert any negative exponents to positive exponents by moving them to the denominator.
3a5b−2=3a5b23a^5b^{-2} = \frac{3a^5}{b^2}
Standard mathematical notation requires final answers to be expressed using positive exponents.

Anahtar Kavram

Applying exponent rules (power, product, and quotient) with numerical coefficients and negative integers.
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