You are right. We can make the derivative with respect to x equal to 0 to find the x value (20 in this case). But the students who take the SAT haven't necessarily taken a Calculus class and are not familiar with principles such as differentiation (derivatives). Remember everyone from 9th graders to 12th graders take the SAT.
1. Try to finish all 6 practice exams in the Bluebook App if you haven't done it already 2. Take a look at the test bank questions (especially hard ones) from CollegeBoard found here satsuitequestionbank.collegeboard.org/ 3. Check out my other videos dealing with hard problems (these questions are from the test bank) 4. Search for previous SATs as well and see if you can do the hard problems. The hard problems are generally toward the end of each section for the non-digital previous version of the test.
Use the question bank to pull from harder problems. I solved every one in this video in my head except for the very last problem.
Thank you for the suggestion. My other videos in the hard problems series have been pulled from that question bank. Please check them out.
6:50 we can just calculus and the derivative of the function for this
You are right. We can make the derivative with respect to x equal to 0 to find the x value (20 in this case). But the students who take the SAT haven't necessarily taken a Calculus class and are not familiar with principles such as differentiation (derivatives). Remember everyone from 9th graders to 12th graders take the SAT.
@@stemtutor365 oh yeah right btw I’m going for SAT this Saturday any tips for maths section ?
1. Try to finish all 6 practice exams in the Bluebook App if you haven't done it already
2. Take a look at the test bank questions (especially hard ones) from CollegeBoard found here satsuitequestionbank.collegeboard.org/
3. Check out my other videos dealing with hard problems (these questions are from the test bank)
4. Search for previous SATs as well and see if you can do the hard problems. The hard problems are generally toward the end of each section for the non-digital previous version of the test.
Two minutes and no mention that a numbs over seven that equals the same number over 9 must be zero? This is not helpful.