问题
计算题
当x=﹣3时,代数式ax5+bx3+cx﹣8的值为6,试求当x=3时,ax5+bx3+cx﹣8的值.
答案
解:当x=﹣3时,
代数式ax5+bx3+cx﹣8=﹣243a﹣27b﹣3c﹣8=6;
∴﹣243a﹣27b﹣3c=14,
即243a+27b+3c=﹣14,
∴当x=3时,
ax5+bx3+cx﹣8=243a+27b+3c﹣8=﹣14﹣8=﹣22.
当x=﹣3时,代数式ax5+bx3+cx﹣8的值为6,试求当x=3时,ax5+bx3+cx﹣8的值.
解:当x=﹣3时,
代数式ax5+bx3+cx﹣8=﹣243a﹣27b﹣3c﹣8=6;
∴﹣243a﹣27b﹣3c=14,
即243a+27b+3c=﹣14,
∴当x=3时,
ax5+bx3+cx﹣8=243a+27b+3c﹣8=﹣14﹣8=﹣22.