更新時(shí)間:2024-01-12 16:35:05作者:貝語(yǔ)網(wǎng)校
解不等式2(x-5)-3(4x+6)>0,開(kāi)始出現(xiàn)錯(cuò)誤的步驟是
A.2x-10-12x+18>0
B.2x-12x>18+10
C.-10x>28
D.x<
A
根據(jù)解不等式的步驟檢查則可.
解答:2(x-5)-3(4x+6)>0,
去括號(hào)2x-10-12x-18>0,
A選項(xiàng)是2x-10-12x+18>0,在去括號(hào)時(shí),18的符號(hào)沒(méi)有改變.
故選A.
點(diǎn)評(píng):本題考查了不等式的解法,解答這類題學(xué)生往往在解題時(shí)不注意去括號(hào)時(shí)符號(hào)的變化這一點(diǎn)而出錯(cuò).