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krishna239455
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what is the value of a^4-b^4?
1. a^2-b^2 = 16
2. a+b = 8
Is this the correct way of solving this problem?
1. a^4-b^4 can be written as (a^2+b^2)(a^2-b^2).
2. Since we know the value of (a^2-b^2), lets think of (a^2+b^2)
3. (a+b)^2 = a^2 + b^2 + 2ab. To get rid of 2ab, add this eqn with (a-b)^2 = a^2 + b^2 - 2ab.
4. We will get the value of (a-b) from (a^2-b^2) = (a+b)(a-b).
The value is 34*16=544
1. a^2-b^2 = 16
2. a+b = 8
Is this the correct way of solving this problem?
1. a^4-b^4 can be written as (a^2+b^2)(a^2-b^2).
2. Since we know the value of (a^2-b^2), lets think of (a^2+b^2)
3. (a+b)^2 = a^2 + b^2 + 2ab. To get rid of 2ab, add this eqn with (a-b)^2 = a^2 + b^2 - 2ab.
4. We will get the value of (a-b) from (a^2-b^2) = (a+b)(a-b).
The value is 34*16=544
