GWD 17-08

[harass]

Q8:
A certain right triangle has sides of length x, y, and z, where x < y < z. If the area of this triangular region is 1, which of the following indicates all of the possible values of y ?

A. y > 根號2
B. 根號3/2< y < 根號2
C. 根號2/3 < y < 根號3/2
D. 根號3/4 < y <根號2/3
E. y < 根號3/4

ANS: A

怎麼算滴?

[zazer.lin]

Q8:
A certain right triangle has sides of length x, y, and z, where x < y < z. If the area of this triangular region is 1, which of the following indicates all of the possible values of y ?

A. y > 根號2
B. 根號3/2< y < 根號2
C. 根號2/3 < y < 根號3/2
D. 根號3/4 < y <根號2/3
E. y < 根號3/4

ANS: A
怎麼算滴?

題目給定一個面積為 1 的直角三角形, 且 x < y < z, 所以可知 x 和 y為該直角三角形的兩股.
面積: xy/2 = 1 ==> xy = 2
又因為 y > x ==> y[sup]2[/sup] > xy = 2 ==> y > 根號2

[harass]

Q8:
A certain right triangle has sides of length x, y, and z, where x < y < z. If the area of this triangular region is 1, which of the following indicates all of the possible values of y ?

A. y > 根號2
B. 根號3/2< y < 根號2
C. 根號2/3 < y < 根號3/2
D. 根號3/4 < y <根號2/3
E. y < 根號3/4

ANS: A
怎麼算滴?

題目給定一個面積為 1 的直角三角形, 且 x < y < z, 所以可知 x 和 y為該直角三角形的兩股.
面積: xy/2 = 1 ==> xy = 2
又因為 y > x ==> y[sup]2[/sup] > xy = 2 ==> y > 根號2

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