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Find the value of n when: ( i ) 5^(2n)...

Find the value of n when:
( i ) `5^(2n) xx 5^(3)=5^(9)`
( ii ) `8 xx 2^(n+2)=32`
( iii ) `6^(2n+1) div 36=6^(3)`

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Let's solve the given questions step by step. ### Part (i): **Equation:** \( 5^{2n} \times 5^{3} = 5^{9} \) **Step 1:** Use the property of exponents that states \( a^m \times a^n = a^{m+n} \). \[ 5^{2n + 3} = 5^{9} \] **Step 2:** Since the bases are the same, we can equate the exponents: \[ 2n + 3 = 9 \] **Step 3:** Solve for \( n \) by isolating it. Subtract 3 from both sides: \[ 2n = 9 - 3 \] \[ 2n = 6 \] **Step 4:** Divide both sides by 2: \[ n = \frac{6}{2} \] \[ n = 3 \] ### Part (ii): **Equation:** \( 8 \times 2^{n+2} = 32 \) **Step 1:** Rewrite 8 and 32 as powers of 2. We know that \( 8 = 2^3 \) and \( 32 = 2^5 \): \[ 2^3 \times 2^{n+2} = 2^5 \] **Step 2:** Again, use the property of exponents: \[ 2^{3 + n + 2} = 2^5 \] \[ 2^{n + 5} = 2^5 \] **Step 3:** Equate the exponents since the bases are the same: \[ n + 5 = 5 \] **Step 4:** Isolate \( n \) by subtracting 5 from both sides: \[ n = 5 - 5 \] \[ n = 0 \] ### Part (iii): **Equation:** \( \frac{6^{2n+1}}{36} = 6^{3} \) **Step 1:** Rewrite 36 as \( 6^2 \): \[ \frac{6^{2n+1}}{6^2} = 6^3 \] **Step 2:** Use the property of exponents for division \( \frac{a^m}{a^n} = a^{m-n} \): \[ 6^{(2n + 1) - 2} = 6^3 \] \[ 6^{2n - 1} = 6^3 \] **Step 3:** Equate the exponents: \[ 2n - 1 = 3 \] **Step 4:** Solve for \( n \) by adding 1 to both sides: \[ 2n = 3 + 1 \] \[ 2n = 4 \] **Step 5:** Divide both sides by 2: \[ n = \frac{4}{2} \] \[ n = 2 \] ### Summary of Solutions: - (i) \( n = 3 \) - (ii) \( n = 0 \) - (iii) \( n = 2 \)
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RS AGGARWAL-EXPONENTS -EXERCISE 5A
  1. Write each of the following in power notation: ( i ) frac(5)(7)xxfra...

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  2. Express each of the following in power notation: ( i ) frac(25)(36) ...

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  3. Express each of the following as a rational number: ( i ) (frac(2)(3...

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  4. Express each of the following as a rational number: ( i ) (4)^(-1) ...

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  5. Find the reciprocal of each of the following: ( i ) (frac(5)(8))^(4)...

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  6. Find the value of each of the following: ( i ) 8^(@) ( ii ) (-3)^(...

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  7. Simplify each of the following and express each as a rational number: ...

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  8. Simplify each of the following as a rational number: ( i ) (frac(4)(...

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  9. Express each of the following as a rational number: ( i ) 5^(-3) ( ...

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  10. Simplify: ( i ) [{(frac(-1)(4))^(2)}^(-2)]^(-1) ( ii ) {(frac(-2)...

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  11. By what number should (-5)^(-1) be multiplied so that the product is (...

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  12. By what number should 3^(-3) be multiplied to obtain 4?

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  13. By What number should (-30)^(-1) be divided to get 6^(-1) ?

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  14. Find x such that (frac(3)(5))^(3) xx (frac(3)(5))^(-6)=(frac(3)(5))^(2...

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  15. (3^5xx10^5xx25)/(5^7xx6^5)

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  16. Simplify: frac(16 xx 2^(n+1)-4 xx 2^(n))(16 xx 2^(n+2)-2 xx 2^(n+2)).

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  17. Find the value of n when: ( i ) 5^(2n) xx 5^(3)=5^(9) ( ii ) 8 xx...

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  18. If 2^(n-7) xx 5^(n-4)=1250, find the value of n.

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