Math 1321 – Exam I – September 20, 2001 Name ___________________________________ 1. Let A(a, b) and B(c, d) be endpoints of some segment AB. Use the coordinates of AB – a,b,c,d to write down the formula a) to find the midpoint of AB b) to find the point P(x,y) that is 4/5ths of the way from A to B. c) to find the undirected distance from A to B d) slope of the line segment AB 2. Write down these other formulas a) the quadratic formula used to solve equations of the form ax2 + bx + c = 0 x = b) the angle of intersection of two lines with slope m1 and m2 respectively. Describe m2. tan = c) distance from the line ax + by + c = 0 to the point P( r, q) ( HINT: use coordinates of P ) 3. Fill in the blank A _________________________ is a relation in which no ordered point of the relation has the same first coordinate but different second coordinate. If represents the angle of inclination of a given of a line then the _____________ of the line is defined as tan . A function f is said to be _____________ provided f( - ) = f( ) A function f is said to be ___________________ on some interval I provided f(x1) < f(x2) for every x1 < x2 in the interval I. 4. Draw a rectangular coordinate system a) label the axes, the quadrants and b) plot the points A ( - 4, 6 ) and B ( 0, - 2 ) 5. Find the length of the hypotenuse of a right triangle that has vertices A(1, 1), B(4, -1), and C(3, 4) _____________________ Find its area = ___________ 6. Determine whether the following three points line are on the same line or not A( 2, - 2 ), B ( - 1, - 6 ) and C ( 4, 4 ). Show Work 7. Complete the following right triangle. 8. A point on the x-axis is known to be equidistant from A(3, -1) and B( -5, 7) . Find the point - both coordinates ! 9. Which one he following terms best satisfies the statement “ a parallelogram with adjacent sides perpendicular “ parallelogram, rectangle, quadrilateral triangle, rhombus, 10. Find each of the following absolute values. Simplify by using the idea of absolute values. Exact values - no calculators. a) | 5 - \/ 17 | = ________ b) | 8 - 3 | = ________ square 11. line with slope m = \/ 3 intersects a vertical line at what acute angle ? ________________ 12. What is the angle of inclination of a line with m = - 1 ? _________________ 13. Draw a triangle with sides ABC, where A is the vertex at the origin, mAB = 1/2, mBC = -4, and mAC = - 2 Find the measure of the largest angle. 14. Identify as just RELATIONS or more specific - FUNCTIONS . a) y = | x | b) x2 + y2 = 16 c) y = x2 + 2x - 1 14.5 Draw each of the following a) x = - 2 b) y = 2x + 4 15. Identify each of the following lines as ; vertical, horizontal, slant, or not a line _________________ a . y = - 4 __________________b. x = 3y _________________ c. x2 = 1 – y 15.5 Identify each of the following as a circle , a point, no graph, or a line _______________ a. ( x+ 2)2 - 16 = - ( y + 2 )2 _______________ b. ( x – 3 )2 + ( y – 2)2 = 0 16. What is the center and the radius of a circle with a diameter AB, where A(2, - 3) and B( -2, 0 ) 17. Give a description of the graph of ( x + 2)2 + ( y – 4 )2 = 4 17.5 Find the equation of the circle with center at ( 2, 0 ) and radius \/ 5 18. Use determinants to find one of the following two problems ( Clearly tell which one your are doing - cross out the other one )-- Show work on the back of previous page a) find the equation of the line that passes through the points ( 2, -3 ) and ( 4, 1 ) or b) Find the area of the triangle with vertices A(2,1), B(3, 2) and C( - 2, 0 ) 19. Find the slope of the line that a) is parallel to the x-axis and passes through the point ( -2, 2 ). _________________________ b) is perpendicular to y = 3x – 2 and passes through ( 0, 2 ). __________________________ 20. Find the equation of the line that a) passes through ( 2, 0) and ( 0, 4). ___________________ b) is parallel to x + 2y = 1 and goes through the origin. ____________ c) is a member of the family y – 2 = m( x + 3 ) and has an undefined slope. ______________ 21. Identify as even, odd, or neither a) f(x) = 2x b) f(x) = 4x + 2 22. Prove that if c > 0 and f(x) = cx + 2 , then f(x) is increasing. 23. Prove the following statement by using an analytic proof --Do not use proofs from geometry. Prove the diagonals of a rhombus are perpendicular. 25. A backpacker looks through a ground telescope at a height of 5 feet and sees the reflection of a mountain top in a pool of water 440 feet in front of him. The mountain is known to be 10560 feet away from the pool. How high is the mountain ? 26. A person 6 feet tall is standing near a street light so that he s 4/10 of the distance from the pole to the tip of his shadow. How high above the ground is the lightbulb ? If the person’s head is exactly 5 feet from the lightbulb, how far is the person from the pole ? 28. What is the distance between the lines 3x + 4y = 12 and 3x + 4y = 24 ?