what is the value of (a^4) - (b^4)?
1. (a^2) - (b^2) = 16
2. a=b=8
qa is c
however cant see to get the meaning of (a^2)+(b^2)
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simba12123
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dally_gmat
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2nd Statement says a= b = 8, So we know for sure a^4 = 8^4 = B^4 therefore b should be sufficient.
1st statement does not answer the question, hence insufficient.
Where I am going wrong?
1st statement does not answer the question, hence insufficient.
Where I am going wrong?
simba12123 wrote:what is the value of (a^4) - (b^4)?
1. (a^2) - (b^2) = 16
2. a=b=8
qa is c
however cant see to get the meaning of (a^2)+(b^2)
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rohangupta83
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i concur with dally_gmat
second statement should be sufficient
a^4 - b^4 upon simplifying gives us
(a-b)(a+b)(a^2+b^2)
a=b=8
will give us
(a-b)(a+b)(a^2+b^2) = 0
imo B
second statement should be sufficient
a^4 - b^4 upon simplifying gives us
(a-b)(a+b)(a^2+b^2)
a=b=8
will give us
(a-b)(a+b)(a^2+b^2) = 0
imo B
You seem to have changed the statement 2 of the question simba. Statement 2 actually reads " a+b=8 " and with this statement one can solve only a part of the answer and thus combining the statements gets the answer C.simba12123 wrote:what is the value of (a^4) - (b^4)?
1. (a^2) - (b^2) = 16
2. a=b=8
qa is c
however cant see to get the meaning of (a^2)+(b^2)
