Let f(x)=2x^4+x^3+x^2-3x+r. For what value of r is f(2)=0?

For every corresponding pair of cross sections, the area of the cross section of a sphere with radius r is equal to the area of the cross section of a cylinder with radius and height 2r minus the volume of two cones, each with a radius and height of r. a cross section of the sphere is and a cross section of the cylinder minus the cones, taken parallel to the base of cylinder, is the volume of the cylinder with radius r and height 2r is and the volume of each cone with radius r and height r is 1/3 pie r^3. so the volume of the cylinder minus the two cones is therefore, the volume of the cylinder is 4/3pie r^3 by cavalieri's principle. (fill in options are: r/2- r- 2r- an annulus- a circle -1/3pier^3- 2/3pier^3- 4/3pier^3- 5/3pier^3- 2pier^3- 4pier^3)

Is 0.8 a rational or irrational number

Anne found the 10th term of the following sequence. her steps are shown below. 3, 7, 11, 15, … 1. common difference = 4, a1 = 3 2. an = 3 + (n - 1)4 3. an = 3 + 4n - 4 4. an = 4n - 1 5. a10 = 4(10) – 1 6. a10 = 39 analyze anne’s work. is she correct? if not, what was her mistake? yes, she is correct. no, she needed to find the common ratio because it is a geometric sequence. no, she substituted the wrong values into the rule to find the equation that represented the sequence. no, she solved for the 10th term incorrectly.