第5課單項(xiàng)式乘以多項(xiàng)式第十四章整式的乘法與因式分解第5課單項(xiàng)式乘以多項(xiàng)式第十四章整式的乘法與因式分1新課學(xué)習(xí)6a3-12a52x-2y-2x+2y-2新課學(xué)習(xí)6a3-12a52x-2y-2x+2y-22知識點(diǎn).單項(xiàng)式乘以多項(xiàng)式am+bm+cm知識點(diǎn).單項(xiàng)式乘以多項(xiàng)式am+bm+cm3-6x2+18xy6a3b2-10a3b3

10a5-3a4

-6x2+18xy6a3b2-10a3b310a5-3a4410a2b2+6a3b2-x3y-2x2y2-a3b+2a2b2

10a2b2+6a3b2-x3y-2x2y2-a3b+2a256a4-10a2b+2a2

-x3y-6xy+2x6a4-10a2b+2a2-x3y-6xy+2x62x3-2x2+6x3x3y3-x2y4+xy3

2x3-2x2+6x3x3y3-x2y4+xy37原式＝（3x2y-2xy2）·（729x18y12）＝2187x20y13-1458x19y14．原式＝（3x2y-2xy2）·（729x18y12）8單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件9原式＝-8a6b3·（3b2-4a+6）＝-24a6b5+32a7b3-48a6b3．原式＝-8a6b3·（3b2-4a+6）10單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件11重難易錯解：原式＝3x2-x3+x3-2x2+1＝x2+1，把x＝3代入得x2+1＝9+1＝10．重難易錯解：原式＝3x2-x3+x3-2x2+1＝x2+1，12解：原式＝x3-x2y+xy2-x2y-xy2-y3＝x3-2x2y-y3.把x＝1，y＝1代入得x3-2x2y-y3＝-2.解：原式＝x3-x2y+xy2-x2y-xy2-y3＝x3-13三級檢測練一級基礎(chǔ)鞏固練C三級檢測練一級基礎(chǔ)鞏固練C14DD15二級能力提升練原式＝2a·3a-2a·2b＝6a2-4ab．二級能力提升練原式＝2a·3a-2a·2b＝6a2-4ab．16原式＝-3x·2x2-3x·（-x）-3x·4＝-6x3+3x2-12x．原式＝-3x·2x2-3x·（-x）-3x·417單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件18原式＝-6x3y+2x2y2-8xy3.原式＝-6x3y+2x2y2-8xy3.19單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件20原式=（4a3-2a+1）·4a2＝16a5-8a3+4a2．原式=（4a3-2a+1）·4a2＝16a5-8a3+4a221三級拓展延伸練解：原式＝6a4b-4a3b2-10a4b+15a3b2-5a2b＝-4a4b+11a3b2-5a2b．三級拓展延伸練解：原式＝6a4b-4a3b2-10a4b+22單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件23解：∵計算一個多項(xiàng)式乘以-2a時，抄錯運(yùn)算符號，算成了加上-2a，得到的結(jié)果是a2+2a-1，∴這個多項(xiàng)式為a2+2a-1-（-2a）＝a2+4a-1.∴正確的計算結(jié)果是-2a·（a2+4a-1）＝-2a3-8a2+2a.解：∵計算一個多項(xiàng)式乘以-2a時，抄錯運(yùn)算符號，算成了加上-24解：由題意可得x2-4x+1-（-3x2）＝4x2-4x+1，則計算正確的結(jié)果為-3x2·（4x2-4x+1）＝-12x4+12x3-3x2．解：由題意可得x2-4x+1-（-3x2）＝4x2-4x+125謝謝！謝謝！26第5課單項(xiàng)式乘以多項(xiàng)式第十四章整式的乘法與因式分解第5課單項(xiàng)式乘以多項(xiàng)式第十四章整式的乘法與因式分27新課學(xué)習(xí)6a3-12a52x-2y-2x+2y-2新課學(xué)習(xí)6a3-12a52x-2y-2x+2y-228知識點(diǎn).單項(xiàng)式乘以多項(xiàng)式am+bm+cm知識點(diǎn).單項(xiàng)式乘以多項(xiàng)式am+bm+cm29-6x2+18xy6a3b2-10a3b3

10a5-3a4

-6x2+18xy6a3b2-10a3b310a5-3a43010a2b2+6a3b2-x3y-2x2y2-a3b+2a2b2

10a2b2+6a3b2-x3y-2x2y2-a3b+2a2316a4-10a2b+2a2

-x3y-6xy+2x6a4-10a2b+2a2-x3y-6xy+2x322x3-2x2+6x3x3y3-x2y4+xy3

2x3-2x2+6x3x3y3-x2y4+xy333原式＝（3x2y-2xy2）·（729x18y12）＝2187x20y13-1458x19y14．原式＝（3x2y-2xy2）·（729x18y12）34單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件35原式＝-8a6b3·（3b2-4a+6）＝-24a6b5+32a7b3-48a6b3．原式＝-8a6b3·（3b2-4a+6）36單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件37重難易錯解：原式＝3x2-x3+x3-2x2+1＝x2+1，把x＝3代入得x2+1＝9+1＝10．重難易錯解：原式＝3x2-x3+x3-2x2+1＝x2+1，38解：原式＝x3-x2y+xy2-x2y-xy2-y3＝x3-2x2y-y3.把x＝1，y＝1代入得x3-2x2y-y3＝-2.解：原式＝x3-x2y+xy2-x2y-xy2-y3＝x3-39三級檢測練一級基礎(chǔ)鞏固練C三級檢測練一級基礎(chǔ)鞏固練C40DD41二級能力提升練原式＝2a·3a-2a·2b＝6a2-4ab．二級能力提升練原式＝2a·3a-2a·2b＝6a2-4ab．42原式＝-3x·2x2-3x·（-x）-3x·4＝-6x3+3x2-12x．原式＝-3x·2x2-3x·（-x）-3x·443單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件44原式＝-6x3y+2x2y2-8xy3.原式＝-6x3y+2x2y2-8xy3.45單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件46原式=（4a3-2a+1）·4a2＝16a5-8a3+4a2．原式=（4a3-2a+1）·4a2＝16a5-8a3+4a247三級拓展延伸練解：原式＝6a4b-4a3b2-10a4b+15a3b2-5a2b＝-4a4b+11a3b2-5a2b．三級拓展延伸練解：原式＝6a4b-4a3b2-10a4b+48單項(xiàng)式乘以多項(xiàng)式(人教版)八年級數(shù)學(xué)上冊課件49解：∵計算一個多項(xiàng)式乘以-2a時，抄錯運(yùn)算符號，算成了加上-2a，得到的結(jié)果是a2+2a-1，∴這個多項(xiàng)式為a2+2a-1-（-2a）＝a2+4a-1.∴正確的計算結(jié)果是-2a·（a2+4a-1）＝-2a3-8a2