can someone help me please im a bit lost. thanks :)
#derivatives
unkempt swift
idle masonBOT
spark quiver
cant you just subsititute the y = (x-1)^2 into the formula x+2y = 2, because the missing point has the equal value ? -> solve: x + 2 * ((x-1)^2) = 4 ; x
not quiet sure if its right tho
ah and: "show that the line is the normal to the curve at one of these point"
dont know what they want
unkempt swift
i know how to find the point of intersection but i just drk the last past
nevermind i fgured it out
spark quiver
can you show the result ?
unkempt swift
do you want me to tell you how i did it?
unkempt swift
yeah
okay so the first part is asking for the points of intersetion. which you already know how to do, (2,1) and (-1/2,9/4).
the second part is asking to show that that straight line is the normal to the curve at one of those points. The gradient of a normal is the negative reciprocal of the gradient of a tangent (as the normal is perpendicular to the tangent).
From this, we first have to find the gradient of the parabola at one of those points. For me, I chose point (2,1). To find the gradient, you differentiate the parabola which is y' = 2x - 2. You then substitute the x co-ordinate (2) into the equation to find the gradient. That equals 2.
And we know the gradient of the straight line is -1/2 if we rearrange the equation. So therefore, the straight line is the normal to the curve at point (2,1) as it is negative reciprocal of the tangent.
idk if i explained that well. if you dont understand i can show you on paper if you want
spark quiver
nah its good, now i understand it... at first i didnt quiet understand the question but now i understood, thx. In the end you ended up helping me in a certen way xd
unkempt swift
.close