Review and consolidate

1.( 1)S=V/h, which is an inverse proportional function; (2)y=S/x, which is an inverse proportional function.

2.b, its k value is -√5/3.

3.( 1) >, decrease by (2)

4.∵y is the inverse proportional function of X, ∴y=k/x, ∴x=k/y, so X is also the inverse proportional function of Y.

Comprehensive application

5.y is the inverse proportional function of z, ∴y=k/z (1).

And ∵z is the inverse proportional function of x, ∴z=k 1/x (2).

Substituting formula (2) into formula (1) gives y=k/k 1/x, that is, y=kx/k 1.

∴y is a proportional function of X.

6.y is the inverse proportional function of z, ∴y=k/z (1).

And ∵z is a proportional function of x, ∴z=k 1x (2).

Substitute formula (2) into formula (1) to get y = k/k1x.

∴y is the inverse proportional function of X.

7.( 1)∵2 is the ordinate of the intersection of the image with positive proportional function y=x and the image with inverse proportional function y = k/x.

∴ There is 2=x, 2 = k/x.

∴x=2,k=4

The analytical formula of inverse proportional function is y = 4/x.

When x=-3, y=4/x=4/-3=-4/3.

(2) From y=4/x, x=4/y is obtained.

When -3 < x

∴-4 √ 2。

The value range of the constant w is w > ∴ 2.

(2)∵ The image of inverse proportional function y=(w-√2)/x is located in the first and third quadrants.

∴ in each quadrant, y decreases with the increase of x, because A(a, b) and b(a', b') are any two points on the hyperbola, and b > b'.

∴a