Question
What must be subtracted from $a^2+b^2+$ lab to get $-4 a b+2 b^2 ?$
✓
Answer
We get, the required result by subtracting
$- 4ab + 2b^2$ from $a^2 + b^2 + 2ab$
$= a^2 + b^2 + 2ab - (- 4ab + 2b^2)$
$= a^2 + b^2 + 2ab + 4ab - 2b^2$
$= a^2 + b^2- 2b^2 + 2ab + 4ab$
$= a^2 - b^2 + 6ab$
$- 4ab + 2b^2$ from $a^2 + b^2 + 2ab$
$= a^2 + b^2 + 2ab - (- 4ab + 2b^2)$
$= a^2 + b^2 + 2ab + 4ab - 2b^2$
$= a^2 + b^2- 2b^2 + 2ab + 4ab$
$= a^2 - b^2 + 6ab$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
In the given figure, $AB \| CD$. If $\angle BAC =(3 x+15)^{\circ}$ and $\angle ACD =(2 x+45)^{\circ}$, find the value of $x$.
Also, find the measures of $\angle BAC$ and $\angle ACD$.
→Also, find the measures of $\angle BAC$ and $\angle ACD$.
Evaluate: 16 + 8 ÷ 4 - 2 x 3
Evaluate : $\frac{-13}{8}+\frac{7}{16}+\frac{-3}{4}$
→Find the excess of $4 m^2+4 n^2+4 p^2$ over $m^2+3 n^2-5 p^2$
→Evaluate: 6 – 8 – (- 6) ÷ 2
Add: $\frac{-7}{24}$ and $\frac{-5}{48}$
→The diameter of a circle is $42 \mathrm{~cm}$, find its perimeter. If the perimeter of the circle is doubled, what will be the radius of the new circle? (Take $\pi=\frac{22}{7}$ )
→Simplify: $b\left(2 b-\frac{1}{b}\right)-2 b\left(b-\frac{1}{b}\right)$
→If A = {even numbers less than 12},
B = {2, 4},
C = {1, 2, 3},
D = {2, 6} and E = {4} then
State if the following statement is true
C ⊆ A
B = {2, 4},
C = {1, 2, 3},
D = {2, 6} and E = {4} then
State if the following statement is true
C ⊆ A
Find whether the given division forms a terminating decimal or a non-terminating decimal:
0.56 ÷ 0.11
0.56 ÷ 0.11