Evaluate, Using (A + B)(A - B)= A2 - B2. 4.9 X 5.1

Evaluate, using (a + b)(a - b)= a² - b².
4.9 x 5.1

Sum

4.9 x 5.1
= (5 - 0.1) x (5 + 0.1)
= (5)² - (0.1)²
= 25 - 0.01
= 24.99.

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Chapter 3: Expansions - Exercise 4.1

Chapter 3 Expansions
Exercise 4.1 | Q 6.3

Evaluate the following using identities:

117 x 83

Find the value of 27x³ + 8y³, if 3x + 2y = 20 and xy = \[\frac{14}{9}\]

Find the value of 64x³ − 125z³, if 4x − 5z = 16 and xz = 12.

Find the following product:

Find the following product:

(3x − 4y + 5z) (9x² +16y²+ 25z² + 12xy −15zx + 20yz)

Use identities to evaluate : (97)²

Expand the following:
(3x + 4) (2x - 1)

Simplify by using formula :
(x + y - 3) (x + y + 3)

Evaluate the following without multiplying:
(1005)²

If x + y = 1 and xy = -12; find:
x - y