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Welcome to numerid.
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In the current problem, we are about to find the derivative of the given curve y equals to 2x minus x squared.
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And we also have to find the slope or the tangent.
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Okay, we have to find the slope of the tangent at the given point.
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Minus 1 minus 3 and also we have to sketch this.
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So with no further delay we will start by defining this as fx.
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Now for definition we know limit h tends to 0 f of x plus h minus f of x divided by h.
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Correct so we have to start by finding f of x plus h which is 2 into x plus h minus x plus h whole square which is equals to 2x plus 2h minus x square minus 2xxxxxx minus h minus h therefore, f of x plus h minus f of x would be 2x plus 2h minus x squared minus 2xx minus 2x minus h squared minus 2x minus h squared.
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Minus this entire 3 .2x plus x minus x squared.
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So this will be minus 2x plus x squared.
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So this term, this term and this term and this term would cancel.
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So we would be left with 2h minus 2 x h minus h square.
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Taking h common we would have 2 minus 2x minus h.
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Therefore then if we divide the left -hand equation by h that is fx plus h minus fx by h we will also be having 2 minus 2x minus h as if that h and that h comes in the denominator that h and divided by h cancels out each other but now if we find what is d by d x so d by d x is equal to limit h tends to 0, f of x plus h minus, that is this expression, f of x divided by h.
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That is, limit h tends to 0, we write the entire expression.
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Now, we will write it by term by term limits.
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Limit of a constant minus limit of a, what should i say? yes, because when we are taking limits with respect to the variable h, everything else is a constant.
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So, wherever we get h, we will substitute those places by h becoming negligibly small, which is about to be zero.
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So, here h have no role to play, so we get 2 minus.
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Here also h has no role to play hence to x, but this term will vanish because as h tends to 0, this entire expression tends to 0.
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So right doesn't change in everything.
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Now, with this understanding is the derivative at point.
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So this is the expression for d .y dx and we have to also find d y dx at the point next 1 minus 3.
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Okay, so let us first write a table.
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So here are on x values here are with y values and i generally start by minus 3 minus minus 2 minus 1, 0, 1, 2, 3.
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And we have to evaluate the expression, that is y is equal to 2x minus x square.
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So if i put 0, let's substitute 0...