(-r^2+3r-7)(r^2-7) eching

$$( - r ^ { 2 } + 3 r - 7 ) ( r ^ { 2 } - 7 )$$

Kengaytirish

$$49-21r+3r^{3}-r^{4}$$

Yechim qadamlari

-r^{2}+3r-7 ga r^{2}-7 ni ko'paytirish orqali distributiv xususiyatdan foydalanish.

$$\left(-r^{2}\right)r^{2}-7\left(-r^{2}\right)+3r^{3}-21r-7r^{2}+49$$

7 hosil qilish uchun -7 va -1 ni ko'paytirish.

$$\left(-r^{2}\right)r^{2}+7r^{2}+3r^{3}-21r-7r^{2}+49$$

0 ni olish uchun 7r^{2} va -7r^{2} ni birlashtirish.

$$\left(-r^{2}\right)r^{2}+3r^{3}-21r+49$$

Ayni asosning daraja ko‘rsatkichlarini ko‘paytirish uchun ularning darajalarini qo‘shing. 2 va 2 ni qo‘shib, 4 ni oling.

$$-r^{4}+3r^{3}-21r+49$$

Baholash

$$\left(-r^{2}+3r-7\right)\left(r^{2}-7\right)$$

Yechim qadamlari

-r^{2}+3r-7 ga r^{2}-7 ni ko'paytirish orqali distributiv xususiyatdan foydalanish.

$$\left(-r^{2}\right)r^{2}-7\left(-r^{2}\right)+3r^{3}-21r-7r^{2}+49$$

7 hosil qilish uchun -7 va -1 ni ko'paytirish.

$$\left(-r^{2}\right)r^{2}+7r^{2}+3r^{3}-21r-7r^{2}+49$$

0 ni olish uchun 7r^{2} va -7r^{2} ni birlashtirish.

$$\left(-r^{2}\right)r^{2}+3r^{3}-21r+49$$

Ayni asosning daraja ko‘rsatkichlarini ko‘paytirish uchun ularning darajalarini qo‘shing. 2 va 2 ni qo‘shib, 4 ni oling.

$$-r^{4}+3r^{3}-21r+49$$