Determine coefficient λ so vectors p and q are mutually perpendicular
$begingroup$
p=λa+17b
q=3a-b
|a|=2 , |b|=5 , angle between a & b vector is 120°
I got for vectors a and b
$$
vec{a}=(-1,sqrt{3}) vec{b}=(frac{-5}{2},tfrac{5sqrt{3}}{2})
$$
how do I find coefficient λ ?
vectors
asked Dec 12 '18 at 17:18
fg101fg101
31
$endgroup$
add a comment |
$begingroup$
p=λa+17b
q=3a-b
|a|=2 , |b|=5 , angle between a & b vector is 120°
I got for vectors a and b
$$
vec{a}=(-1,sqrt{3}) vec{b}=(frac{-5}{2},tfrac{5sqrt{3}}{2})
$$
how do I find coefficient λ ?
vectors
asked Dec 12 '18 at 17:18
fg101fg101
31
$endgroup$
add a comment |
$begingroup$
p=λa+17b
q=3a-b
|a|=2 , |b|=5 , angle between a & b vector is 120°
I got for vectors a and b
$$
vec{a}=(-1,sqrt{3}) vec{b}=(frac{-5}{2},tfrac{5sqrt{3}}{2})
$$
how do I find coefficient λ ?
vectors
asked Dec 12 '18 at 17:18
fg101fg101
31
$endgroup$
p=λa+17b
q=3a-b
|a|=2 , |b|=5 , angle between a & b vector is 120°
I got for vectors a and b
$$
vec{a}=(-1,sqrt{3}) vec{b}=(frac{-5}{2},tfrac{5sqrt{3}}{2})
$$
how do I find coefficient λ ?
vectors
vectors
asked Dec 12 '18 at 17:18
fg101fg101
31
asked Dec 12 '18 at 17:18
fg101fg101
31
asked Dec 12 '18 at 17:18
fg101fg101
31
asked Dec 12 '18 at 17:18
fg101fg101
31
asked Dec 12 '18 at 17:18
fg101fg101
31
31
add a comment |
add a comment |
1 Answer
1
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oldest
votes
$begingroup$
Hint: we get
$$vec{p}cdot vec{q}=3lambdavec{a}^2+51vec{a}cdot vec{b}-lambdavec{a}cdot vec{b}-17vec{b}^2$$
and use that $$vec{x}^2=|vec{x}|^2$$
answered Dec 12 '18 at 17:34
Dr. Sonnhard GraubnerDr. Sonnhard Graubner
76.2k42866
$endgroup$
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Hint: we get
$$vec{p}cdot vec{q}=3lambdavec{a}^2+51vec{a}cdot vec{b}-lambdavec{a}cdot vec{b}-17vec{b}^2$$
and use that $$vec{x}^2=|vec{x}|^2$$
answered Dec 12 '18 at 17:34
Dr. Sonnhard GraubnerDr. Sonnhard Graubner
76.2k42866
$endgroup$
add a comment |
$begingroup$
Hint: we get
$$vec{p}cdot vec{q}=3lambdavec{a}^2+51vec{a}cdot vec{b}-lambdavec{a}cdot vec{b}-17vec{b}^2$$
and use that $$vec{x}^2=|vec{x}|^2$$
answered Dec 12 '18 at 17:34
Dr. Sonnhard GraubnerDr. Sonnhard Graubner
76.2k42866
$endgroup$
add a comment |
$begingroup$
Hint: we get
$$vec{p}cdot vec{q}=3lambdavec{a}^2+51vec{a}cdot vec{b}-lambdavec{a}cdot vec{b}-17vec{b}^2$$
and use that $$vec{x}^2=|vec{x}|^2$$
answered Dec 12 '18 at 17:34
Dr. Sonnhard GraubnerDr. Sonnhard Graubner
76.2k42866
$endgroup$
Hint: we get
$$vec{p}cdot vec{q}=3lambdavec{a}^2+51vec{a}cdot vec{b}-lambdavec{a}cdot vec{b}-17vec{b}^2$$
and use that $$vec{x}^2=|vec{x}|^2$$
answered Dec 12 '18 at 17:34
Dr. Sonnhard GraubnerDr. Sonnhard Graubner
76.2k42866
answered Dec 12 '18 at 17:34
Dr. Sonnhard GraubnerDr. Sonnhard Graubner
76.2k42866
answered Dec 12 '18 at 17:34
Dr. Sonnhard GraubnerDr. Sonnhard Graubner
76.2k42866
answered Dec 12 '18 at 17:34
Dr. Sonnhard GraubnerDr. Sonnhard Graubner
76.2k42866
76.2k42866
add a comment |
add a comment |
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