Question

Find a. b. if a =10i+4j and b = 3i+4j

Answer 1

Answer:

10i+4j times 3i+4j=

30i+16j

(30,16)

Step-by-step explanation:

Answer 2

Answer:

Option (c) is correct.

The dot product of given vectors $a=10\hat{i}+4\hat{j}$ and $b=3\hat{i}+4\hat{j}$ is 46.

Step-by-step explanation:

Given : The vectors  $a=10\hat{i}+4\hat{j}$ and $b=3\hat{i}+4\hat{j}$

We have to find the dot product of given vectors a and b

Consider the given vectors $a=10\hat{i}+4\hat{j}$ and $b=3\hat{i}+4\hat{j}$

$\mathrm{Computing\:dot\:product\:of\:two\:vectors}:\quad \left(x_1,\:\:\ldots ,\:\:x_n\right)\cdot \left(y,\:\:\ldots ,\:\:y_n\right)=\sum _{i=1}^nx_iy_i$

We have

$\begin{pmatrix}10&4\end{pmatrix}\begin{pmatrix}3&4\end{pmatrix}$

$=30+16=46$

Thus, The dot product of given vectors $a=10\hat{i}+4\hat{j}$ and $b=3\hat{i}+4\hat{j}$ is 46.