Find the Square of : 3a + 7b

Find the square of : 3a + 7b

Sum

We know that
( a + b )² = a² + b² + 2ab
( 3a + 7b )² = 9a² + 49b² + 2 x 3a x 7b
= 9a² + 49b² + 42ab

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Chapter 4: Expansions (Including Substitution) - Exercise 4 (A) [Page 57]

Chapter 4 Expansions (Including Substitution)
Exercise 4 (A) | Q 1.2 | Page 57

Factorise the following using appropriate identity:

`x^2 - y^2/100`

Write the following cube in expanded form:

(2x + 1)³

What are the possible expressions for the dimensions of the cuboids whose volume is given below?

If \[x + \frac{1}{x} = 5\], find the value of \[x^3 + \frac{1}{x^3}\]

Find the following product:

(3x + 2y) (9x² − 6xy + 4y²)

\[\frac{( a^2 - b^2 )^3 + ( b^2 - c^2 )^3 + ( c^2 - a^2 )^3}{(a - b )^3 + (b - c )^3 + (c - a )^3} =\]

Use the direct method to evaluate :
(0.5−2a) (0.5+2a)

Evaluate: (5xy − 7) (7xy + 9)

If `x^2 + (1)/x^2 = 18`; find : `x - (1)/x`

Simplify:

`(x - 1/x)(x^2 + 1 + 1/x^2)`