Find, using algebra, all real solutions to the equation Watch

kalazoof
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16a^2=2roota (4 marks)
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Gregorius
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(Original post by kalazoof)
16a^2=2roota (4 marks)
What have you tried?
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Teenie2
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Try starting be squaring both sides and that'll get rid of the square root. Rearrange so you have the "a" component on one side and a value on the other.
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Suran23
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Square both sides so you get256a^4=4a. Divide by 'a' on both sides to get:256a^3= 4. Divide 4 by 256 to give:a^3=0.25. Cube root to find 'a' which gives 1
Last edited by Suran23; 3 weeks ago
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mqb2766
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Factorize, don't divide, otherwise you lose solutions.
(Original post by Suran23)
Square both sides so you get256a^4=4a. Divide by 'a' on both sides to get:256a^3= 4. Divide 4 by 256 to give:a^3=0.25. Cube root to find 'a' which gives 1
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dextrous63
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(Original post by Suran23)
Square both sides so you get256a^4=4a. Divide by 'a' on both sides to get:256a^3= 4. Divide 4 by 256 to give:a^3=0.25. Cube root to find 'a' which gives 1
Do NOT divide by a since this is a classic mistake! If you move the right hand side over then you can factorize and get a outside brackets which will give one root of a=0. The rest of Suran's method can then be applied.
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