2.2 直接证明与间接证明（练案一）-2020年高中同步教与学数学（人教B版选修2-2）

书书书 !"# ! $%&'( !!! ! !"#$%&"#$ !!!!" ! '()%*+) ! " ,- " "! ! " " ! " # "#$ " # $ # "$%&' %&'()*%+, " - # !! $ (! " " " "# # " " " # "# # )! " " " $" # "# % *! " " " " &% " " " # " &" +! " " " $" # "$ % #! ! $ # ' " % # ' . $%, # $$% $ % " " - # !! $ (!$$% % # #槡#$"$ )!$$%&槡#$" *!$,% & #槡#$"$ # +!$$% # #槡# #$"$ -! /01 -. 23456789:;<6=> " ?!@ &/0 % 1 % ABCD67 ! EF/0G67HIJK %''/0 " LMNOP &34QR(STU & # $ #' # /0 " VW " X;=>NYGD67 %Z[\Q" # !! $ (! #'' - 1 )!"21 *!"#1 +!#%1 %! P] & $ # $% # ,",$ # % # & ' " ^P]_ # !! $ (!#$%,",$ # % # & ' )!$ # $% # ,", $ % $% % # & ' *! # $$% $ # # ,",$ # % # & ' +! # $ # ," $# % # ," $ % ' 3! ! $ " % ' # $ " '&槡$$槡%"(& $$槡 %"-'"(%`TabL # !! $ (!' % ( )!' & ( *!' # ( +!' $ ( 4! c " # $ ) # &"'" d:e # 3 " - $ f * gh " ij%KBkl*m no " Z[%hKLnopq $ " " ZK%hKLno%rq $ * " sHm + ' " - " ' ( " # " - * %tuvw" # !! $ (!*&% )!3 & * & . *!* # . +!* ' # $ .! xyz ,-'(./ %{|L}#~ " ,/ ( �| '(./ " ,/& '/&" " !e . G�| ,'( %R�L $ " e ( G�| ,'. % R�L % " -f # !! $ (!" $ $ $ % )!$ # % # " *!$ $ " $ % +!% $ $ $ " 2! �:�+n " " (*� " # $$ " " " $" % ' �l� " -+n $ %t uvw" # !! $ (! # , 5 " ,# ( )! ' ,# " # ( *! ' ,# " $ 5 $ +! ' ' " $ 5 $ 6! s��� # �%���n 0 # " $ &$" # ,%$"$% �7Q ' ' " # ( �"��n " . 0 # 1 $ % 0 # ' $" -+n 1 %tuvw" # !! $ (!' & 1 & % )!' & 1 & # *!1 & ' +!1 & ' � 1 % % "'! ) '(. %��K $ ! % ! 2 %�nl*mno " �] & * ( $ 6'7! ""! EF 89: ! " 89: " ! ;<8 " %*m�q " 89: # " 89: " ! ;<8 " %* ��q ! �] & ;<8% # ,%;<8% ! &-! ) " ) !" !!! #$ !!!!!!!!!!!!!!!!!!!!!!! %&'()*+ ! ,- " . # /0 !!!!! ! .#) ! " ,- " "! �1�]�����%��c$�P��o� ¡Lg¢£ 1 # !! $ ! ¤¥)�¦§ " ¨?! * " ©ª«%g¢ * # H¬ ! �¬ ! � �* * $ ©¤¥ ! (! !" )! !"$ *! !"# +! "# #! ª« + ) '(. � " s * ' #* ( " - $ # % , %¤¥%­��®" # !! $ (!$ $ % )!$ & % *!$&% +!$ % % -! ª« + aU " %#$ $"&% # $ + ' $ %¯"°:% , %¤¥%­ �" # !! $ (! ±¯ )! &¯ *! ²³&¯ +! ±¯�²³&¯ %! ª« + �´~�Zµ^f:'d´"C´ , %¤¥%­�" # !! $ (! f&'d´"C´ )! f�'d´"C´ *! ²³f&'d´"C´ +! ¶f:'d´"C´ 3! ! " " ) " 3 ' # ' " $ 5 $" -�n "$ " ) " ) $ " 3 " 3$ " " � # !! $ (!