Question

Plzzz answer it fast...... ​

Answer 1

$\boxed {\begin {minipage}{3cm}\large\mathsf {a+b=\pm1.5}\\\\\large\mathsf {a^2-b^2=\pm1.35}\end {minipage}}$

Given,

• $\displaystyle\sf {a-b=0.9}$

• $\displaystyle\sf {ab=0.36}$

Then,

(i)

$\displaystyle\longrightarrow\sf {a+b=\sqrt{(a+b)^2}}$

$\displaystyle\longrightarrow\sf {a+b=\sqrt{a^2+2ab+b^2}}$

$\displaystyle\longrightarrow\sf {a+b=\sqrt{a^2-2ab+b^2+4ab}}$

$\displaystyle\longrightarrow\sf {a+b=\sqrt{(a-b)^2+4ab}}$

$\displaystyle\longrightarrow\sf {a+b=\sqrt{(0.9)^2+4(0.36)}}$

$\displaystyle\longrightarrow\sf {a+b=\sqrt{0.81+1.44}}$

$\displaystyle\longrightarrow\sf {a+b=\sqrt{2.25}}$

$\displaystyle\longrightarrow\sf {\underline {\underline {a+b=\pm1.5}}}$

And,

(ii)

$\displaystyle\longrightarrow\sf {a^2-b^2=(a+b)(a-b)}$

$\displaystyle\longrightarrow\sf {a^2-b^2=\pm1.5\times0.9}$

$\displaystyle\longrightarrow\sf {\underline {\underline {a^2-b^2=\pm1.35}}}$

Answer 2

Answer:

2) a2-b2

answer......

a−b=0.9

Squaring both sides,

=>(a-b)^2=(0.9)^2

a^2+b^2-2ab=0.81

=>a^2+b^2=0.81+2(0.36)

=>a^2+b^2=1.53

Again,

(a+b)

2=a2 +b2 +2ab

=1.53+2(.036)

=1.53+0.72

=2.25

=>a+b={2.25}

=±1.5

Now,

(a2 −b2 )=(a+b)(a−b)

=±(1.5)(0.9)

=±1.35

1) a+b

answer.....

a+b = root of (a+b) whole square

= root of [(a-b)^2 +4ab ]

= root of (0.9)^2 +4×0.36

= root of (0.81+1.44)

= root of 2.25

= 1.5

so a+ b = 1.5

so a+ b = 1.5and a2-b2 = 1.35

hope it will help you..........