Calculus
posted by Judy .
The point P(4,2) lies on the curve y=x^1/2
If Q is the point (x,x^1/2) use your calculator to find the slope of the secant line PQ for the following values of X:
1)3.5
2)3.9
3)3.99
4)3.999
5)4.5
6)4.1
7)4.01
8)4.001
i plugged these points into the intial equation and got that it was approaching 2. and i made it the slope of secant. however, my friend got a different answer; she found the slope using delta y over delta x. who is right and why?
thanks for any help!

4) If the coordinates of Q are
x = 3.999, y = 1.99975
then the slope of the "secant" line between Q and P (4,2) is
(.00025)/.001 = 0.2500 = 1/4
The exact value of the slope of the tangent to the y(x) curve at P is dy/dx = (1/2)/sqrt x = 1/4
For points Q farther from P, you will get a slightly different answer
Respond to this Question
Similar Questions

calc so confused
Point (5,3) lies on curve y=sqrt(x+4). If Q is the point (x,sqrt(x+4)), use your calculator to find the slope of the secant line PQ for the following values of x. a)x=4.5 I just want help on this one. What do I do? 
Math
The point P(8, −3) lies on the curve y = 3/(7 − x). (a) If Q is the point x, 3/(7 − x)), use your calculator to find the slope mPQ of the secant line PQ (correct to six decimal places) for the following values of … 
calculus
The point P(4, −2)lies on the curve y = 2/(3 − x). (a) If Q is the point(x, 2/(3 − x)),use your calculator to find the slope mPQ of the secant line PQ (correct to six decimal places) for the following values of x. … 
calc
The point P(4, −2)lies on the curve y = 2/(3 − x). (a) If Q is the point(x, 2/(3 − x)),use your calculator to find the slope mPQ of the secant line PQ (correct to six decimal places) for the following values of x. … 
Math
1. The slope of the tangent line to a function at a point is equivalent to __. a. the slope of the secant at that point b. the slope of the cosecant at that point c. the rate of change of the function at that point d. the slope of … 
Math
THE POINT (8,3)LIES ON THE CURVE Y=3/(7X) (a)IF Q IS THE POINT (x,3/(7X)) USE YOUR CALCULATOR TO FIND THE SLOPE OF THE SECANT LINE PQ CORRECT TO SIX DECIMAL PLACES FOR THE VALUE OF X. (i)7.9 Mpq? 
calculus 1
The point P(2,1) lies on the curve y=1/(1x) If Q is the point (x, 1/(1x) find slope of secant line. these are the points 1.5 1.9 1.99 1.999 2.5 2.1 2.01 2.01 2.001 when i calculated it i got a negative number 1/(11.5)=2 but the … 
calculus 1
The point P(2,1) lies on the curve y=1/(1x) If Q is the point (x, 1/(1x) find slope of secant line. these are the points 2, 1 1.5,2 1.9,1.111111 1.99,1.010101 1.999,001001 2.5,0.666667 2.1,0.909091 2.01,0.990099 2.001,0.999001 … 
Math (Secant Lines)
Consider the function f(x)=sqrt(x) and the point P(4,2) on the graph of f? 
calculas
The point P(7, −4) lies on the curve y = 4/(6 − x). (a) If Q is the point (x, 4/(6 − x)), use your calculator to find the slope mPQ of the secant line PQ (correct to six decimal places) for the following values of x. (i) 6.9 …