Question A 04
Shown in the figure below is a function and its tangent line at .
The tangent line intersects the axis at the point . The coordinate of the point is
Make sure you understand the problem fully: What is the question asking you to do? Are there specific conditions or constraints that you should take note of? How will you know if your answer is correct from your work only? Can you rephrase the question in your own words in a way that makes sense to you?
If you are stuck, check the hints below. Read the first one and consider it for a while. Does it give you a new idea on how to approach the problem? If so, try it! If after a while you are still stuck, go for the next hint.
The slope-point form equation of a line with slope passing through is . How can we use the information in the question to find an equation for the tangent line?
By definition, the slope of the tangent line to at is .
Checking a solution serves two purposes: helping you if, after having used all the hints, you still are stuck on the problem; or if you have solved the problem and would like to check your work.
Noting that , we solve for using the equation of the tangent line to at :
which is answer .