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You are not logged in. #1 20051130 04:41:59
More QuadraticsI'm given the function f(x)=(x2)^2+9 and asked for the maximum value (9) and to sketch the graph of y=f(x) showing where the curve crosses the axis. I'm not sure of the standard way to work backwards but I worked back to y = x^2 + 4x + 5 and tried to factorise it to get the points where it crosses the xaxis. Aloha Nui means Goodbye. #2 20051130 06:01:40
Re: More QuadraticsFactorising x² + 4x + 5 gives you (x+1)(5x), so the roots would be 1 and 5. Why did the vector cross the road? It wanted to be normal. #3 20051130 06:06:22
Re: More QuadraticsI know the answer was right, I looked it up Aloha Nui means Goodbye. #4 20051130 08:34:24
Re: More QuadraticsI would personally use the quadratic equation for this problem: #5 20051130 09:09:06
Re: More QuadraticsWow thanks, I'll make my answer a little more specific next time. Aloha Nui means Goodbye. #6 20051201 12:50:29
Re: More QuadraticsI've been using the quadratic formula to solve equations on which I first complete the square. I notice you are using the same formula here but without the sqrt? Aloha Nui means Goodbye. 