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问题: 高一函数题请帮忙,谢谢

1、y=ax∧3+bsinx+1 且f(2)=7 f(-2)=?
2、y=cos(x+π/8)[cos(x+π/8)+sin(x+π/8)]的奇偶性

解答:

1、y=ax^3+bsinx+1 且f(2)=7 f(-2)=?
2、y=cos(x+π/8)[cos(x+π/8)+sin(x+π/8)]的奇偶性
解:
1、
f(2)=8a+bsix2+1=7,所以8a+bsix2=6
则 f(-2)=-8a-bsin2+1=-(8a+bsix2)+1=-6+1=5
(也可以按stare 的做法)
2、
cos(x+π/8)[cos(x+π/8)+sin(x+π/8)]
=[cos(x+π/8)]^2 +cos(x+π/8)sin(x+π/8)
={[1-cos(2x+π/4)]/2}+{sin(2x+π/4)]/2}
=[1+sin(2x+π/4)-cos(2x+π/4)]/2
=[1+(√2)sin2x]/2
=(1/2)+(√2/2)sin2x
所以y既非奇函数也非偶函数