( 1)。 a; (2)。 c; (3)。 a; (4)。 d; (5)。 b; (6)。 a; (7)。 d; (8)。 c; (9)。 c; ( 10)。 d; ( 1 1)。 C.
1 1 explanation: let the coordinate of point b be (x, y); Then the coordinate of point M is (x/2, y/2); The point m is on the image of the inverse proportional function, so it satisfies the equation y=k/x, that is, y/2=2k/x, so xy = 4k...( 1); Quadrilateral area ODBE = rectangular OABC area -△OAD
-the area of △ oce = xy-(1/2) x (k/x)-(1/2) y (k/y) = xy-(1/2) k-(1/2).
( 12)。 b;
12 question answer: from y=( 1/2)x? -2x=( 1/2)(x? -4x)=( 1/2)[(x-2)? -4]=( 1/2)(x-2)? -2, so this is y=( 1/2)x? Image of
An image obtained by panning 2 units to the right and then panning 2 units down. According to the symmetry of the figure, the area of the shadow part =2×2=4. Of course, it can also be done through integration.