1、 2018 150 120 (10 3 30 ) 1 . A B C D 2 2 3 a b ab b = A 1 3B 1 2C 5 3D 3 53 ABC 1 3 A ( ) A B 1 3C 3 D 4 cos 2 45 sin 2 45 ( ) A. 1 2B 1 C. 1 4D. 2 25 Rt ABC C 90 sin A 2 3 cos B ( ) A. 1 2B. 2 2C. 2 3D 1 6 x 2 y A B. C D 7 ABC |sinA 1 2 | ( 3 3 tanB) 2 0 C ( ) A 30 B 60 C 90 D 120 8 y=ax 2 2ax+c 1
2、0 ax 2 2ax+c=0 A x1= 3 x2= 1 B x1=1 x2=3 C x1= 1 x2=3 D x1= 3 x2=1 9 y= 2 x 4 . 1 23 3 4 5 6 7 8 9 10 A y= 2 2 x +2 B y= 2 2 x 2 C y= 2 2 x +2 D y= 2 2 x 2 10 y ax 2 bx c ( ) A a0 C a b c0 D a b c0 (8 4 32 ) 11 | | 1 tan 12 30 25 5 _ 13 3 2 14 x y z 4 5 7 3x 2y z 2x 3y 2z _ 15 P -1 m m _ 16 2 23 y x
3、 bx 1 x b 17 ABC 90 C 1 sin 2 A 2 AB ABC 18 3.2m 8m 22m m ( 88 ) 19. 8 (1) 4 24 60 sin 45 cos 2 2 2 2 3 30 tan 3 ) 2 ( 0 . 20 6 (0 3) ( 4 11) 21 6 ABC BC 22 8 y=ax 2 +bx+3 x=1 1 2a+b=0 2 x ax 2 +bx 8=0 4 23 8 AC BC F B 0 30 20 E B 0 60 BC 0.1 24 10 1 3 3 m. (1) ( 0.1 m) (2) 30 2 m 25 10 80 /kg 120 /
4、kg. 180 /kg x( /kg) 120 130 180 y(kg) 100 95 70 y x (1) y x x 2 26 10 x A( 2 0) B(4 0) 9. (1) (2) C y D ABCD 27 10 ( ) 28 m ABCD( AB BC ) AB x m S m 2 . (1) S x (2) P CD AD 15 m 6 m ( ) 28 12 A ( 2 0) OB OA AOB (1) B (2) A O B (3) (2) C BOC C 25 (1) 10 5 kg y x y x y 100 0.5(x 120) 0.5x 160. 120 /kg
5、. 180 /kg x 120 x 180. (2) w w (x 80)( 0.5 x 160) 1 2 x 2 200x 12 800 1 2 (x 200) 2 7 200. a 1 2 0 x 200 y x x 180 w 1 2 (180 200) 2 7 200 7 000( ) 180 7 000 26 (1) x 2 4 2 1. 9 C(1 9) y a(x 1) 2 9 B(4 0) a 1. y (x 1) 2 9 y x 2 2x 8. (2) x 0 y 8 y D(0 8) C CE x E S ABCD S AOD S DOEC S BCE 1 2 2 8 1 2 (8 9) 1 1 2 3 9 30. 27 (1) AB x m BC (28 x)m. S x(28 x) x 2 28x. S x 2 28x(0 x 28) (2) x 6 28 x 15. 6 x 13. (1) S x 2 28x (x 14) 2 196. 6 x 13 S x x 13 S 195 195 m 2 .
