NCTB Class 7 Math Chapter Five Exercise 5.2 Solution by Math Expert. Bangladesh Board Class 7 Math Solution Chapter 5.2 “Algebraic Formulaic and Applications” Exercise 5.2 Solution.

Board |
NCTB |

Class |
7 |

Subject |
Math |

Chapter |
5 |

Chapter Name |
“Algebraic Formulaic and Applications” |

Exercise |
5.2 Solution |

__Exercise:- 5.2__

__Exercise:- 5.2__

**(1) Solution:-** (4x+3) (4x-3)

= (4x)^{2} – (3)^{2}

= 16x^{2} -9

**(2) Solution:-** (13-12p) (13+12p)

= (13)^{2} – (12p)^{2}

= 169 – 144p^{2}

**(3) Solution:-** (ab+3) (ab-3)

= (a b)^{2} – (3)^{2}

= a^{2} b^{2} – 9

**(4) Solution:- **(10-xy) (10+xy)

= (10)^{2} – (x y)^{2}

= 100 – x^{2}y^{2}

**(5) Solution:-** (4x^{2}+3y^{2}) (4x^{2}-3y^{2})

= (4x^{2})^{2} – (3y^{2})^{2}

= 16x^{4}– 9y^{4}

**(6) Solution:- **(a-b-c) (a+ b+ c)

= a- (b +c)}{a+ (b +c)}

= {a +(b +c)} {a- (b +c)}

= a2- (b +c)^{2}

= a^{2}– (b^{2}+2bc+c^{2})

= a^{2}-b^{2} -2bc-c^{2}

**(8) Solution:-** (x-1/2a) (x-5/2a)

= x2+ (-1/2a – 5/2a) x + (-1/2 a) (-5/2a)

= x2+ (-a-5a/2)x + 5a2/4

= x2+ (-6a/2)x + 4a2+4

= x2- 3ax + 5/4a2

**(9) Solution:-** (1/4x – 1/3y) (1/4x + 1/3y)

= (1/4x)2 – (1/3y)2

= x2/16 – y2/9

**(10) Solution:-** (a^{4}+3a^{2 }x^{2}+ 9x^{4}) (9x^{4}– 3a^{2} x^{2} + a^{4})

= {(a^{4}+9x^{4}) + 3a^{2} x^{2}} {a^{4}+ 9x^{4}) – 3a^{2} x^{2}}

= (a^{4}+9x^{4})^{2} – (3a^{2}n^{2})^{2}

= (a^{4})^{2}+ 2x2a^{4}x9x^{4}+ (9x^{4})^{2} – 9a^{4}x^{4}

= a^{8}+ 18a^{4} x^{4} + 81x^{8}– 9 a^{4} x 4^{4}

**(11) Solution:-** (x+1) (x-1) (x^{2}+1)

= (x^{2}-1) (x^{2}+1)

= (x2)^{2} – (1)^{2}

= x^{4}-1

**(12) Solution:-** (9a^{2}+b^{2}) (3a+b) (3a-b)

= (9a^{2}+b^{2}) (9a^{2} – b^{2})

= (9a^{2})^{2} – (b^{2}) ^{2}

= 81a^{4} – b^{4}

Where is number 7?

Thank YOU vi

Where is 7????

(x²-x+1),(x²+x+1)

=(x²+1-x)(x²+1+x)

=(x²+1)²-x²

=(x²)²+2.x².1+1²-x²

=x⁴+2x²+1-x²

=x⁴+x²+1