標題:
vector 問題 快..
發問:
1. Let u =4i+3j and v=2i-3j suppose a and b are two real constants and au+bv = 8i+j find the values of a and b2. with respect to O OA=3i-2j OB=6i+4j and OC=kOA , where k is a constant (a) express BC in terms of k i j (b) if BC perpendicular to OA find the value of k3. Given that OA=5i+3j OB=... 顯示更多 1. Let u =4i+3j and v=2i-3j suppose a and b are two real constants and au+bv = 8i+j find the values of a and b 2. with respect to O OA=3i-2j OB=6i+4j and OC=kOA , where k is a constant (a) express BC in terms of k i j (b) if BC perpendicular to OA find the value of k 3. Given that OA=5i+3j OB= -7i+9j and p is a point on AB such that AP=2PB find the unit vector in the direction of OP
最佳解答:
其他解答:
vector 問題 快..
發問:
1. Let u =4i+3j and v=2i-3j suppose a and b are two real constants and au+bv = 8i+j find the values of a and b2. with respect to O OA=3i-2j OB=6i+4j and OC=kOA , where k is a constant (a) express BC in terms of k i j (b) if BC perpendicular to OA find the value of k3. Given that OA=5i+3j OB=... 顯示更多 1. Let u =4i+3j and v=2i-3j suppose a and b are two real constants and au+bv = 8i+j find the values of a and b 2. with respect to O OA=3i-2j OB=6i+4j and OC=kOA , where k is a constant (a) express BC in terms of k i j (b) if BC perpendicular to OA find the value of k 3. Given that OA=5i+3j OB= -7i+9j and p is a point on AB such that AP=2PB find the unit vector in the direction of OP
最佳解答:
此文章來自奇摩知識+如有不便請留言告知
(1) au + bv = 8i + j a(4i + 3j) + b(2i - 3j) = 8i + j (4a + 2b)i + (3a - 3b)j = 8i + j 4a + 2b = 8 and 3a - 3b = 1 Solving, we have a = 13/9 and b = 10/9 (2a) BC = BO + OC = OC - OB = k(3i - 2j) - (6i + 4j) = (3k - 6)i - (2k + 4)j (b) BC.OA = 0 [(3k - 6)i - (2k + 4)j].(3i - 2j) = 0 3(3k - 6) + 2(2k + 4) = 0 9k - 18 + 4k + 8 = 0 k = 10/13 (3) By point of division formula: OP = (OA + 2OB)/3 = (5i + 3j - 14i + 18j)/3 = - 3i + 7j Hence |OP| = √(32 + 72) = √58 So the unit vector along OP is (- 3i + 7j)/√58其他解答:
文章標籤
全站熱搜
留言列表
