Photo AI

(a) Write down the value of $125^{ rac{1}{3}}$ - Edexcel - A-Level Maths Pure - Question 3 - 2009 - Paper 1

Question icon

Question 3

(a)-Write-down-the-value-of-$125^{-rac{1}{3}}$-Edexcel-A-Level Maths Pure-Question 3-2009-Paper 1.png

(a) Write down the value of $125^{ rac{1}{3}}$. (b) Find the value of $125^{- rac{2}{3}}$.

Worked Solution & Example Answer:(a) Write down the value of $125^{ rac{1}{3}}$ - Edexcel - A-Level Maths Pure - Question 3 - 2009 - Paper 1

Step 1

Write down the value of $125^{ rac{1}{3}}$

96%

114 rated

Answer

To find the value of 125^{ rac{1}{3}}, we need to determine the cube root of 125. Since 125=53125 = 5^3, we have:

125^{ rac{1}{3}} = (5^3)^{ rac{1}{3}} = 5.

Thus, the value is 5.

Step 2

Find the value of $125^{- rac{2}{3}}$

99%

104 rated

Answer

To find the value of 125^{- rac{2}{3}}, we first convert it to a positive exponent:

125^{- rac{2}{3}} = rac{1}{125^{ rac{2}{3}}}.

Next, we find 125^{ rac{2}{3}}:

  • First, find 125^{ rac{1}{3}} = 5, as calculated earlier.
  • Now, square it:

125^{ rac{2}{3}} = (125^{ rac{1}{3}})^2 = 5^2 = 25.

Thus, we have:

125^{- rac{2}{3}} = rac{1}{25}.

This means the value is rac{1}{25}.

Join the A-Level students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;