Question

In ΔABC, A (1, 0), B (K, 0), C (0, 2) and m∠B = π/( 2) then, find the value of K.​

Answer 1

$\begin{tabular}{|c|c|c|}\cline{1-3}Height (In cm)&No. of Pupil & C.f. \\\cline{1-3}90 - 100 & 5 & 5 \\\cline{1-3}100 - 110 & 2 & 7\\\cline{1-3}110 - 120 & 3 & 10\\\cline{1-3}120 - 130 & 8 & 18\\\cline{1-3}130 - 140 & 8 & 26\\\cline{1-3}140 - 150 & 6 & 32\\\cline{1-3}&\sum\limits f=32&\\\cline{1-3}\end{tabular}$

Answer 2

Given,

Given,The vertices of △ABC are A(1,2,3),B(−1,0,0) and C(0,1,2) then we have to find ∠ABC.

Given,The vertices of △ABC are A(1,2,3),B(−1,0,0) and C(0,1,2) then we have to find ∠ABC.BA→=(1+1)i^+(2−0)j^+(3−0)k^=2i^+2j^+3k^

Given,The vertices of △ABC are A(1,2,3),B(−1,0,0) and C(0,1,2) then we have to find ∠ABC.BA→=(1+1)i^+(2−0)j^+(3−0)k^=2i^+2j^+3k^BC→=(0+1)i^+(1−0)j^+(2−0)k^=i^+j^+2k^

Given,The vertices of △ABC are A(1,2,3),B(−1,0,0) and C(0,1,2) then we have to find ∠ABC.BA→=(1+1)i^+(2−0)j^+(3−0)k^=2i^+2j^+3k^BC→=(0+1)i^+(1−0)j^+(2−0)k^=i^+j^+2k^cosθ=∣BA→∣ ∣BC→∣BA→⋅BC→=4+4+14+4+92+2+6=6