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# C2 Log Question watch

1. Hi, can someone look at this log question(attached). I dont understand what they want me to prove....I need help on both Qc and Qd
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2. (Original post by Bengaltiger)
Hi, can someone look at this log question(attached). I dont understand what they want me to prove....I need help on both Qc and Qd
to do part (c) take 2 to the power of both sides and simplify

then factorise the cubic - I'm guessing that of the three roots it only makes sense to put one of them back into the original equation - say because only one is positive and the others negative
3. Ok, i think i got the idea. But how about the next part.

State, with a reason, the value of x that satisfies equation(I)
4. (Original post by Bengaltiger)
Ok, i think i got the idea. But how about the next part.

State, with a reason, the value of x that satisfies equation(I)
Well as I said, the roots - which are -1, -2, 4 - don't all make sense to put back in the original equation

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